That is great question on the shaft seal . . . I guess I should not complain, I finished the car in 2013 (and have put on 10k miles) and now I see evidence of pag oil on the front of the compressor, so time for the shaft seal to be replaced . . . hence the question, just do the seal (ones today say compatible with R134), or convert to the Sanden rotary . . . but as you say, its all there in place and nothing else wrong . . . probably order up the shaft seal and talk to my local AC shop . . .