The patches I remember were diamond-shaped, and the flaming stuff was made into a diamond metal holder.
I had forgotten the Rema brand, but that's what we used on truck tires when I was working at the dump-truck place. Great stuff. Where can you buy them?
Normal process with the patches: Rough up the tube, apply the cement, let the cement dry, apply the patch, work it down good onto the cement. I normally try to have the tube aired up to the size it is in the tire when I put the patch on. Patches on the inside surface don't often work well.
One issue is that they sell some of the one-size-fits all tubes that have to stretch a lot when they're inflated in the tire, and that makes it harder to get a patch to hold.
This is the bucket of stuff I pulled out of truck tires. Actually, this is only part of it, because about half the flats were due to rocks working their way through, or no object still in place, and I only saved the metal stuff.