Cut the stall mat to 24x32 which is roughly what I measured the tank bottom to be.
The tank has a little bump out on the bottom, probably to act as a sump? I trimmed the center out of the stall mat to clear that. The bump out isn't centered so I just took the smallest measurements and cut the whole a little large. The stall mat is pretty tough and I didn't want uneven pressure because of the little bump out.
Pictured are the painted spacers as well.
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I took a punch and a 3lb hammer to approximately the third thread down inside each spacer. One solid but not super aggressive hit per hole. That will distort just enough to create some mechanical locking and still leave a few threads to get everything started.
Tank is "temporarily permanent" now. I'm was going to do something different so I only had 4 flange bolts and I'd rather have everything matching so I'm going to wait to tighten everything up until I can get 4 more. They will get blue thread locker and anything that gets tight before bottoming out will get a couple washers. I want it to be nice and snug against the rubber but I also want the majority of the force to be against the spacers and not just the bolt. Wouldn't matter for compressive force but I'd imagine 30+gal of fuel sloshing around will be putting some side force on everything and having everything tight against the spacers will stop the bolts from moving around in the threads are eventually wearing them out.
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