[TowerTalk] Stacking Beams

[Don Tucker]

Looking for feasibility advice.

Have one tower, a HyGain HG-70HD.

Currently have a 7 el TH7DX tribander right at the tower top with a  3 el 
A3WS duobander 8 feet above it. No noticable interactions.

Have acquired a Cushcraft XM240 2 el shorty forty. Would like to put in on 
the same mast as the latter two.

What is the best placement of the these (bottom, middle and top) and what is 
the minimum separation I can get away with between them? E.G., 40 on the 
bottom, the TH7 middle and  12/17 top, or????  Or will this all be too much 
for a single HD mast/TX2 rotator?

Don W7WLL