Greets!

A triangle is best, then one with angled sides, but Olson's work indicates up to 10.5" regular depth was acceptable, so 12" is a bit much.

Anyway, from your drawing I take it that you're not interested in a three cab MTM?

?? Unless you make ducted ports like on the Ultraflex you can't put them on the rear and still shove it hard into the corner. Regardless, unless you need long ports to get the desired tuning (which you probably won't) there's no advantage to them other than cosmetic.

Thanks again for the thought! My BD 'gift' to me was a ~$200 repair bill to get the truck to pass emission testing. If the economy wasn't so bad, I'd sell the thing and find me a pre-1985 truck that I can diagnose myself rather than being scammed since it turns out that all that was needed was the MAF sensor being spray cleaned!

GM