The "trick" as everyone knows, is finding someone that's actually good with a motor. While all engines do basically the same thing and don't know what brand they are, each one DOES have its quirks & finding someone that knows them & can work with/around them is tough. Chevys almost everywhere are the most numerous so you'll get alot of people who know about them. The other brands, fewer in number, take a little more effort & searching. BUT if you find a good, say Ford machinist, you'll probably have a good motor. Here in Phoenix, I know of 2 seperate shops I'd take a Ford motor to,depending on the engine. There's tons of Chevy guys around here so that's not an issue. But a Mopar, B-O-P? Good Luck! Hell, I even know a good AMC guy here so even that one isn't an issue.
Back then P/S was a developing class so advancements were coming by leaps & bounds so guys guarded their "secrets" closely. Today streetracing can be won or lost at the drop of a nitrous pill or a change of a blower pulley so in some ways it's easier. Back then it actually took brains & skill to win at streetracing as the majority were N/A so you had a reason to be proud & boast! Sadly that isn't the case any more......