Daw - Cooool post. I am big Mercedes fan and just recently sold my Euro Spec W124 Sportline E320 which was the last year for the twin cam straight six, 24V WITH variable valve timing (218hp and 220ft.lbs)
I think the 3.2L V6 are good engines and replaced the decades of Mercedes and their legendery straight six designs.
I would love to hear about your conversion of your 380SEC from the 3.8L V8 to the 3.2L V6. Personally I think the 3.8L V8 is very anemic, so I am glad you are not going to bother with it. $500 is a steal good for you - WOW!
I almost recently bought a 1989 560SEC, which I think is one of the sexiest cars still after being 20years old. Pillarless, long and sleek....mine would be lowered with 18" AMGs and that would be it....yum!
I know I nuts....but this is my second fav. Benz of all time, 450SEL 6.9:
Yasin