Best place to cut rocker box for...

[Bigb55]

What would be the best place to cut the rocker box for access to the rear cargo tub? I need to get in there to mount a backer plate for a rollbar in my '74?

I was thinking of cutting out a square where the inspection holes are on the rear plate. Just big enough to fit the backer plate and a ratchet. Then welding some flat iron across it for support.

Any better ideas? Would the bottom plate of the box be better? Only other option is welding the hoop legs to the floor.

I tried to access the rear cargo floor when doing my floor pan repair up front, but no go.

 

[mechted]

Yeah, right through the angled section you pictured is where I cut. Don't have to fit a rachet, box end wrench with the nuts taped in place is lower profile and just as easy to get positioned. Or weld the nuts to the backing plate so they can't move.

Ended up with a 2" high x 4" wide hole, and used a slightly bigger cover plate that I just used tec screws to install. Then rubberized undercoating to seal it. Hole was small enough that I didn't worry about the box flexing

 

[Bigb55]

Yeah, right through the angled section you pictured is where I cut. Don't have to fit a rachet, box end wrench with the nuts taped in place is lower profile and just as easy to get positioned. Or weld the nuts to the backing plate so they can't move.

Ended up with a 2" high x 4" wide hole, and used a slightly bigger cover plate that I just used tec screws to install. Then rubberized undercoating to seal it. Hole was small enough that I didn't worry about the box flexing

did you cut the square out through both holes or just one of them? Or right In the middle of them?

I'm guessing it probably doesn't matter. Just as long as something gets put over the hole to keep it all together. It will be nice to have a big hole to access in there too.

I'll probably weld the nuts onto the backing plate.

I had enough fun balancing the body mount, washer, and nut when I did the mount by the gas tank through the access holes. Still easier then dropping the gas tank though.

 

[mechted]

Think I incorporated the top hole when I cut... cant remember 100%. You just need the access. Use a big magnet on a stick to get the backing plate positioned.