HI. I'M WITH YOU ON THIS ONE.I HAVE NOT DONE A RETROFIT YET. BUT I HAVE REPAIRED ONES THAT HAVE BEEN RETROFITTED. I HAVE CLEANED & RETURNED OTHER RETROFITTED ONES BACK TO R-12. I BELEAVE THE 134A TO BE CORROSIVE ON A RETROFITTED SYSTEM. I JUST HAD A (1983 I TH... Login to read more.