I'm not sure if it was a proper conversion or not, but I'm inclined to think it was since all work was done at the Mercedes dealership and everything looks very clean. The original owner was an older lady who passed away a year ago and had the car since new, then her grandson inherited it and occasionally used it. Judging by the receipts, whatever the dealer suggested she do, so just handed them her gold card. Very wealthy family. The car has 209,000 miles on it, but I'm thinking it's mostly highway and/or longer trips since the family lives on the outskirts of town in a rural farming area. It's a 1988 and silver-blue with blue leather. Leather has zero rips and just needs some Tanner's Preserve to hydrate it. Transmission shifts smoothly except yesterday when it randomly flared from 2-3 (I think) for a split second a couple times, but I think it's low on tranny fluid. I just ordered a bunch of parts (dash mat, cup holders, side marker lights, headlight doors, tow hook cover, driver's seat switch, 4 new door puddle lights, etc) and need to get a new plastic grill insert too. Maybe URO or something. The Becker Grand Prix tape deck works, but the radio stations are dead silent. It's the model that doesn't have the separate "brain" in the trunk, so must be built in. But yeah, I don't know of anyone who does r12 here in the valley, but my mechanic definitely works with r134a. Any physical differences I could be able to make out by just glancing up at the expansion valve to figure out if it's been changed? - Mike