I got a couple of sets of these super cool lake header pipes that work perfect for your project or can be run in what ever configuration you wish. there are a ton of different options. not sure of the gauge steel but there thinker then my speedway ones but not too think like a 36 driveshaft. they measure 19.25 long with an inlet of just under 1.75 and an exterior of 2.75 with an internal "baffle washer" of 1.5/8 that can be removed if you wish. $65 shipped in the US for a pair. Paypal only