Made a simple but solid/rugged mounting system for my LJ Hard Top.
I did this on my old 88 YJ and was really pleased with it. The idea behind this is to spread the load on the hardtop mounting surface so no single point of the fiberglass is asked to bear the entire load should any form of incidental contact happen off road or otherwise.
In short one of the more common things I saw with other Jeeps was the fiberglass around the bolts would crack or wear at a much higher rate due to the pressure put on the glass whether from overtightening, contact offroad (trees, etc..) or anything else really.
Anyhow, I'm rambling. On with the info...
1"x36"x1/8" Alluminum, holes made with 3/8" drill bit
Forget the length on the Eye Hook bolts, think it's 2.5" but I know diameter is 5/16"
I experiemented with both single/double nut at the top to square up the mounting surface. Single Bolt seems to be the best if you want to use a double washer system on the underside of the bolt.
Top and Bottom I used a regular washer as well as a rubber washer.
I also used a nylon threadded nut to secure the bolts, could just as easily use locktite if you want.
Total Hardware investment about $20