I'm struggling to get much information on this as it's not a very common modification, but I'm really interested in doing it for various reasons. If I'm correct (from what I've seen), you use the stock subframe but replace:
Control Arms (Wishbones)
Hubs (Uprights)
Track Rods + Ends
Optional: Steering Rack (with above)
I have all the part numbers for the TT RS here (the various different assemblies I need):
http://vagpart.com/audi/audi-ttrs-coupe-roadster-ttrs-eu-2010-front-axle-steering/Just trying to document all the info in one place and get anyone who knows more to point me in the right direction of what needs to be done and where to source parts from. Also, I'll need to work out things like which SuperPro bushes to use throughout (makes sense to do those while the parts are on the work bench).
Current plan is to build up both axles as much as possible off the car and then just swap entire assemblies into the car for ease of fitting, haven't made much attempt as working out parts on the rear axle just yet (one at a time). Any pointers would be amazing.