Si, it well easy to remove the exhaust you got two bolts at back of cat convertor and a couple of rubbers the hard bit is twisting the exhaust enough to get it off at the back near the subframe shouldn't need any welding unless you stick a universal back box on the original exhaust, ease depends if your is a one piece exhaust from cat back..... better if split like mine.... if one peice car needs to be high up preferrably on a lift ramp thingy to twist it out...
Then you just need to unclip the the hand brake cable running to the n/s rear wheel just let it sag a bit dont disconnect it. Then just thread new exhaust through, as i said before you'll probably have to twist the whole exhaust round to get it through should be ok on ramps not sure as mine was on a lift 6ft in the air so i was standing under mine when i did it.