long story short, i dont think i have the original engine that came with the truck in 2008. My engines casting number says 234, and when i looked it up it says 4.3L vortec boat engine. Is there a way to figure out which 4.3L vortec boat engine i have? i have to fix a cylinder 6 misfire and can't depend on standard 08 silverado engine info since its a boat motor.