It would also depend on it the truck was fully assmbled in the factory or was purchased as a glider and finished by an outside upfitter. Basically, you can paint it almost any color and justify it being that way.
Due to MPC being out of business for almost 30 years, no, they never made a kit with modern tooling methods. But, they did make some good kits that stand up well today, the 69 Olds Casey mentioned being among them. It has a multi piece suspension front and rear with separate exhaust so it's close to newer kits. Their heavy truck kits like the DM600 and DM800 are noticeably crisper than their AMT counterparts as well. It's best to try to find a parts breakdown to see if it's something you would be interested in.
The Detail Junkies engine linked to is the engine that is the Welderup show car, it's a 5.9 Cummins 12 valve from a Dodge 3500 truck. I also scratch built a Detroit 4-53, I built the block and oil pan and borrowed the gear covers from an 8v-71 from a semi kit.
I don't care for A, B, or C completely. None of them stay consistent to their design theme, I don't like modern components on rat rods. I like the chop and drilled visor on B but the car is a bit too grungy for me but has chrome engine pieces. Give me C chopped like B with C's vintage engine and find some more period looking wheels and tires.
Mike, I thought the same thing about the store at University. It was huge and did all the gaming stuff and rc stuff but they closed about two years ago. I don't know why Charlotte can't keep a hobby store in business, it doesn't make any sense.
I noticed that too Mike and I meant to message you about it. I stopped there a lot and spent more than I want my wife to know about. I had talked to David at one point and he said he made most of his money off of rc stuff so I thought they were going to be around for a while. For me it's going to be the Hobbytown in Mooresville, Rock Hill is too far out of the way.