hmm... never seen this forum before.
Hey man, since this board doesn't even list the 124, and so far nobody has responded to your post, if you need tech support for a 124 you need to come to http://www.mirafiori.com/ .. a US based forum that deals with keeping alive the cars we got from FIAT while they were here selling cars.
Yes, removing the starter is necessary... disconnect the ground strap on the battery first, starter wires can stay connected. Top bolt is a little hard to see, but if you loosen the front motor mounts and jack the engine up at the bellhousing it will come into view. Makes it easier to get to as well. Extensions and swivels and you'll get there.
Once removed it can be rested in place somewhere around that area.. don't let it hang from the wires, lots of these connectors are corroded and weak -- old cars.
To remove the trans, spend a few minutes and remove the shift lever. Small access cap right there above the guibo will reveal springs and cups. When it comes back to reassembly time, it helps if you bolt the plastic bearing to the trans -without- the metal cap, that way a friend can compress the shift lever and you can get that nut threaded on there... then unscrew the plastic piece, slap the cap over it and put your screws in.
Don't forget, you've got a reverse light switch and probabally and emmissions 3rd/4th gear switch on the trans -- disconnect them before you try pulling it or you'll have a torn harness.
Good luck.
- Matt