questions regarding conversion to r134a- what o-rings need to be replaced, other ???s

[Bene]

Just slap 'er back together with some new O-rings and charge the system with propane. System will blow unimaginably cold air, and it'll likely never leak again as the propane molecule is much larger than the freon molecule.

Just be real careful not to get in an accident! ;)

[Kershaw]

i thought mythbusters proved that even if you have a puncture, propane wont explode.

its only when you mix fire and propane that things go badly. and most accidents dont have fires.