The front edge has the most depth clearance for the tank & fuel…

The front edge has the most depth clearance for the tank & fuel lines, so I cut it 1st. The lip (visible in the front L hole) juts rearward ~1/8" here, but I cut both layers. The front edge of the hole can be an inch or so behind the welds to avoid the lip of the floor support channel. You can always cut the hole too small, and then enlarge it as-needed. But if you cut it too large, the plate won't cover the hole, so always start small.

A slitting chisel in an air hammer is a FAR-BETTER way to cut the hole, and doesn't require any prep.

Owner caption June 2009 · Photo 2510 of 6546