Ok, some updates:
So, here is the first wheelbarrow load of gravel I dumped into the frame. I want to offer a word of thanks to xoB for helping me with the idea of the blocks as a ramp. I got the idea from his help on an old thread about my car ramps. Still, I hadn't forgotten. Thanks xoB!
Anyhow, DUMP!
More dumping.
Lots more dumping and screeding and tamping. Looks good doesn't it?!