The (first?) Chevy Diesel was a Dud?!?

[Tigger]

Hello Everybody

Hello, I am new here with an old truck. But I am not new to old vehicles.
A few years back I purchased a 78 chevrolet DIESEL from the original owner which some may recall came from the factory with an Oldsmobile 350 Big Block and a TH400 transmission. I did a search and found no info on this model, so please direct me if I am in the wrong location.
The engine was a dud because it was frankensteined by G.M, smoked alot and gave the previous owner mostly grief. He converted the Oldsmobile back to gasoline while keeping the original manifolds and exhaust pipes. I have since put a New carburetor on it with electric choke.This truck has only 47,000kms (less than 30,000 miles) with original paint . I've been stopped a few times because she still shines when washed on a nice summer's day .
My Question/Dilema :: The Oldsmobile has enough torque to pull stumps out of earth sideways and is a great working engine but it was GM's least efficient motor! This is the problem. I am interested in converting the nice body to a modern Chevy/GM vortex driveline. Are there any experts out there that can share their wisdom on this conversion??
Am I crazy to do this to an older truck or pass it on to someone who appreciates originality?? I restore old racecars and do custom fabrication so I do respect original hardware alot. The truck has an 8 foot box and still perfect white C H E V R O L E T lettering on the tailgate. One classy Truck!!

Thanks,

Rob Martel

www.robmartel.com
http://photos.yahoo.com/sunbeambob