OK Jerry here is the BD4 version. I like the rear
beam better. Also I added shims so the downthrust
angle can be adjusted.
-- 
Paul Lamar ...No rotor no motor.

Paul,  can you tell me the over length of the rear beam measured
along its center line?   I think I can get it out of a 4 foot length
but not sure.  I want to order steel today if possible.    Jerry

Sure here it is.
-- 
Paul Lamar ...No rotor no motor.

I get so tired of asking piddly little questions  and I definitely
feel like a pest, but the witness lines for the outer arms of the
beam dimension indicating a length of 16.87" do not appear to go to
the end of beam.    Jerry

Your are right. They go to the center of the intersection.
Add an inch on for each side when you figure material.
Still less than four feet.

I can send you an iges for your cad program.