All good advice above. The inner joint is much less likely to need replacing. Have you checked it for wear? If not, There's two easy ways to check it. One way is to get a helper to sit behind the steering wheel with the lock disengaged - so ignition switch in the normal running position so the steering lock is not engaged. Now lie on the ground and use one hand to feel for the inner joint by compressing the rubber bellows. Then get your helper to rock the steering back and forth enough that it makes the front wheels move a little while you feel for movement between the tie rod and the end of the rack ie, movement in the ball joint. There should be non and it's not difficult to feel if there is as it "jumps". The other way, especially if you don't have a helper, is to jack the wheel off the ground - support the car on an axle stand please - and grip the wheel at the quarter to three position. Now try to rock the wheel back and forward. If there's play in the joint you'll soon feel it and if the play is any more than slight you'll see the movement. It's important that there is no free play at all. It's completely impossible to set the toe with any play here. In fact play anywhere whether it's here, in a track rod end, a bottom ball joint, etc will all make toe adjustment a meaningless exercise. While you're doing this carefully watch the end of the rack. Is it jumping up and down, rather than going in and out. Up and down movement indicates wear between the rack itself and the housing it runs in. Some racks can be adjusted at the pinion end but, frankly, if there's wear there you'll probably never satisfactorily adjust it out and on the non pinion end it's going to be worn bushes - a new/exchange recon rack is the best solution. However, when I was on the "shop floor" renewing track rod ends was a very frequent job and the MOT bay ensured a steady flow of candidates, The number of inner joints reported could be counted on the fingers of one hand in a month or longer. The inner joints are well protected by the bellows and in an oily environment. Track rod ends live a much harder life.
If you do need to undo the inner joint then, as mentioned above, it's just the fact the rack has a bit of a flat side where the teeth are meshed with the pinion which stops the rack rotating in it's housing. As people are saying above, they're usually not all that tight so worth giving it a try. However if it's looking like you're really going to have to lean into it then, as said above, it does worry me that you may damage either the pinion or it's bearings - which are small and not very robust or even the rack housing and if you do that then there will be play between the rack and housing which would mean a replacement rack! I have a roll of robust strapping which I use for making slings etc from and I've always thought if I was faced with it then I'd wrap a couple of turns of that round the end of the rack and get a grip on it with one of my medium size Stilsons, hoping that the strapping would protect the rack at the same time as giving the Stilsons something to grip on (the rack is hardened so the Stilsons might be reluctant to grip it) To date I've never had to do this at home and in the workshop we tended to fit a new rack complete when ever anything other than track rod ends were needed. If that seems a bit extreme, then our experience was that by the time the inner joints were worn out there were often other problems like lift in the rack and/or play in the pinion and/or that the rack was "dry" and maybe somewhat dirty because someone in the past had fitted a new rubber boot/gator/whatever you call them without properly cleaning the dirt which had perhaps entered due to the old bellows being torn. When working professionally you've got to consider time, which equates to cost and also the possibility that if you miss existing damage the job may well come back to bite you in the derriere and end up in no profit on the job as well as an unhappy customer. Fitting a new rack overcomes that.
Seized track rod ends? An everyday problem for any garage. A nice big club hammer, mine's a 4lb jobbie, or other substantial chunk of metal - and a 1 lb ball pein hammer are my favourite weapons of choice. With the wheel off the ground - axle stands - and the wheel removed Place the club hammer against one side of the threaded part of the track rod end - or it's lock nut if that's what you're trying to free off - and start hammering on the other side with the smaller hammer. You don't need to hit it so hard it leaves impressions on the metal but it does need to be more than a "love tap". Do this repeatedly for a wee while. How long? depends on how badly corroded it is. You may need to reposition the club hammer so you can hit it from a different side. It's mainly the shocking effect and that you are very slightly "squeezing" the threaded fitting which loosens it. Some releasing fluid, like Plus gas for instance, might also help. If you've done this for a while and it's not slackening then some heat - in the garage we had Oxy Acetylene which is VERY HOT but at home, from something like a plumbers hand held butane/propane blow torch gets the job done - It needs to get hot, but doesn't need to glow red hot. Throwing some cold water over it to "shock" it often helps too. Once you've got the thread freed up then count the number of turns it takes to remove the track rod end and screw the new one on by the same number of turns. This is most unlikely to result in correctly adjusted toe because manufacturing tolerances differ between brands and even batches, but it will be good enough for you to drive to the nearest workshop who has the equipment to adjust it properly - and, because you've done all the hard work freeing up the rod ends, there's unlikely to be any "excess charges" for freeing up frozen fittings. Also, because all the adjustments can be made easily, you're much more likely to end up with everything set up as it should be rather than "bodged" because the worker couldn't be bothered to free off a seized fitting. It does happen folks, I've seen it more than once.
