I have a '78 CJ5 that I bought back in 1987. It was a rusty hulk and a few years later I bought a fiberglass tub for it. I was a young PFC in the Army and cost was the deciding factor. I've hated the fiberglass body from day one snd here's why:
You hated it after you finished all of the work?
The body is about 1/4 - 3/8 inch narrower that the original which means my OEM hood and windshield frame doesn't marry up well and I have to build spacers to put between the winshield hinges and body.
I have this issue with my "no name" tub. I thought it was the hood that was slightly wider as it had been damaged. I managed to get it centered well enough that you don't notice it, but it had to be in the sweet spot.
While grounding isn't a difficult issue to solve, it is time consuming and some things are not as easy to ground as others.
Something you deal with when you decide rust is no longer in your future.
There is a tremendous amount of flex in the body where the windshield attaches causing the top of the windshield to move back over an inch when at highway speeds. This has always been a safety concern for me.
I can see this happening on some tubs. There are obviouosly different quality tubs available, and I would say mine is the lesser. The mounting points for the windshield (at the hinges) had cracked out from wind forces. The PO apparently was not bothered by this. I had to repair this area, and my windshield is braced by the A pillar.
The firewall and cowl seam was very poorly done and needed significant re-engineering to keep it together and make it so it didn't look horrible.
I thought this area was completely ridiculous on my tub! The two pieces are pop-riveted together. PO squirted Liquid Nails, or something, to make better adhesion. I placed a strip of glass along that seam and solved it. Solid and no air leak.
I made a template of the firewall of my steel body to help with cutting the fiberglass fenderwell and it helped but the thickness f the firewall still made it necessry to build custom brackets. I realize they now sell these that you then have to add.
I think that would be understood and expected.
I had to build custom rollbars. The OEM didn't fit between the fender rails due the body being narrow and the heavier lip wouldn't allow the angle iron to fit under it.
My factory rollbar was very, very tight, and I forced it out when I rebuilt the tub. Since it was for my kid there was no way I was going to let him roll down the hiway in a piece of glass without a cage. I didn't mind doing this, and a full cage EXPLODES the COOL factor by 1000!
Anywhere something mounts to the body needed custom backing plates for support - fenders, hood hinges, windshield hinges, dashboard, seat and seatbelt mounts, etc.
There was no bracket for the e-brake and no real way to attach a bracket to the side of the tub that either didn't look bad for the bolts goingthrough the body and the mass of glass that would have needed to be added.
Didn't install mine.
I have no doubt fiberglass tub quality has improved since then and I find myself tryimng to decide again between fiberglass and steel as I plan a full rebuild. Cost isn't a factor anymore but time and effort is and after scouring everything I can find talking about both, given all the issues with the steel tubs I'm still leaning in that direction.
Love to see it when you are done.
Welcome to the Forum! Thank you for your service.