Nick, with the washers on top nobody will see them when the body is mounted. I would consider mounting them from below, so they can be seen after the car is assembled.
Can the tank be removed with the bolts coming in from the top Once the body is mounted ?
1955 2 DR Post
1937 Chevy Coupe
2023 Ford Super Duty F350 TREMOR
2019 Corvette Z06
1955 Chevy Nomad
1935 Ford 2dr Slant back I have 4