· 92 TURBO
@Woosh10 is correct, the old black seals and O rings will not hold up to R134a refrigerant. The green and the Toyota red O rings will work with either R12 & R134a.I'll let the more knowledgeable give you the definitive answer.. but I think the old R12 seals just wouldn't hold up to R134a. You might be fine with those greens ones for R12 though. I just can't give you a definitive answer.
@SupraMikeCT, this question seems right up your alley.
Green manifold gasket for the MK3's Supra ND 10PA17 compressor manifold when converting to R134a:
BTW, I would use Ester oil instead of PAG if I were converting to R134a. Ester oil is more compatable with any remaining mineral oil than PAG oil.
The desiccant used in new receiver/driers also work for both refrigerants