Hey brad I did what binkowski suggested and found the c-clamp style but with short threaded tightener. It was on page 3 for me. I'm sure you could doctor one to YOUR specs.

 

I am WAY ahead of you guys......

Already got some flat stock and tube welded together and bolted in place of the faculty tie down point.

Then I took a standard cap clamp apart and used the bottom side along with some 3/8 threaded rod.

All it is doing is bending the threaded rod

 

The clamps suck if you go offroad with any regularity because they loosen up. They also destroy the cap over time if you don't put a piece of something on top of the cap rail to spread the load. Wearing their way through the cap also loosens them up but more slowly than offroading. The clamps build for truck caps and covers are much better than just plain C-clamps though.


Self tapping sheet metal screws suck even worse because they're a rust magnet and you need a million fended washers to spread the load enough to not pull through the cap and even if they don't pull through the cap they don't have enough area to do a more than marginal job holding to the bed rail so you have to use a ton of them (and drill a ton of holes in the bed rail. You also can't reuse them more than once or twice before the holes they go into strip out.


When I get around to permanently mounting my cap on my pickup trailer I'm going to drill and tap some aluminum blocks with three or four 3/8 bolt holes and drill matching holes in the bed rail and a piece of scrap hardwood on top of the cap rail to spread the load and keep the bolt heads from working their way into the fiberglass. You could use the same scraps of hardwood on the bottom instead of metal but drilling and tapping a metal block makes it possible to attach the cap over a bed liner that goes over the top of the bed rail.


Yes you can use clamps or self tapping screws and get away with it but IMO it won't last very long unless you drive like a grandpa on smooth roads and you'll have to re-do it every few times you bump a tree/post/whatever. When I brought my cap home the C clamps loosened up and it was only a few miles of normal roads and the handful of times I've used the cap it's loosened up or shifted (using two clamps from a tonneau cover and four c clamps) and my truck doesn't have a bed liner that goes over the rails.


I don't think those are factory. I've never seen them in any truck but I also haven't seen that many flare-sides compared to normal beds. They do look pretty useless though since their footprint is so small any forward load will bend the sheet metal below them really quickly.


I can't fathom not running a bed liner

 

Well, I lucked out..
I called my local cap place and they had a set of 4 on the shelf covered in 20 years of dust. They were so nice they even sold them to me for cost since they figured no one else was going to call looking for them.

For $24 and a ride with the dog and I have my problem fixed.

I'll try and get a pic of them, they are a little different than the ones steel horse posted

 

Gives the meaning for new old stock. That's awsome. Glad it worked out