That sounds like a real nice "Blue Chip Money Maker" as they used to call 'em. I think 55 is the first year it could have come stock with a V8. It would have been a Pontiac 287.
Goob, Don't know if this might be of any help to you, but, my '55 2nd series 3100 has a Pontiac 400 with Muncie 4 speed. Runs great, loads of low end. I bought the truck with this engine in it, and the guy I got it from knew nothing about it either. Fits in nice, exhaust clears steering, small amount of dishing of firewall at left valve cover. A couple of C channel cross members were used for front engine mounts and rear tranny tailshaft mount. '56 auto car driveshaft from Muncie to stock rearend. Looks like the engine grew there! Must have some kind of mild cam, nice lope at idle. Holly manifold with Edelbrock 600cfm carb. Carb is outstanding. Good luck with your project!
