All but the rear forks

Here's the view from head on ...
You can see the front forks (purple), Bottom Bracket for the front crank (silver), the front derailleur post (blue), and the chain rollers (red).

Here's a 3/4 view ...
What's missing are the rear forks at the other end of the main tube.
The plans recommend chromolly tubing bent 90°.
I have EMT tubing, but that didn't seem very strong.
I'm still working on them ...

Here's a right side view ...
the rear forks attach to that left end of the main tube.