When I was making the leading edge cradle for my RV-3B, it had to fit on the leading edge while it was on the jig. This led to rounding the front of it.
The pipe interconnecting the two pieces is simply a 18" length of black pipe screwed into flat ends (using epoxy so they'd stay put).
And it rocks!
When I want it to stay in one position, I simply put a C-clamp on one of the wood pieces and that gives me a third leg.
Incidentally, there's a hidden requirement - the wood pieces should be deeper everywhere so that Clecos don't hit the table. These are.
Dave