How much decking is to much?

I went back and re-read what you wrote and I stand by what I said. You clearly state the shop gave you back a block that was still uneven side to side. They need to find a new profession cause the one they chose don't suit um too well. They told you to rely on different head gaskets. What a effin joke.
Decking parallel and square decking are two different things on the price sheet ;) . That bank will crank even at least ... so they're half way there. Lol ...but i agree with you, I'd have told them to go mill the other side the same and basically chastise them for being lazy and thoughtless.
Amazing.