Alright. Lately with the way my engines been running I dont know what to do. But first things first, the guy who got this car 'rebuilt' i think got screwed. its a 401 amx, but i cant be sure the engine matches unless i find the vin numbers on the block. where are they located? if this engine isnt original, how hard is it to find a 401? Are there any big differences between the 360 and the 401 that might tell them apart from one another?