Hi

I have a bike with mechanical Ultegra 8000 with disc brakes. It has all internal routing.

I also have a spare 8150 rim brake groupset from my warrantied Madone

I’m thinking I could upgrade this bike by buying two 8170 STI levers and putting the rest of the 8150 stuff on there - battery, cables, derailleurs.

Should I be able to leave the existing calipers in place? Or would 8100 calipers be better (servo wave?) - I don’t know how much spare hose there is to re-cut but if I could leave that routed it seems a slightly easier job.