[Wswss] Spacing of mult band beams on one mast

[N3IZN at aol.com]

So I got the foundation set and started stacking the tower. 5 years in the  
makin......
 
Any comments on how close I can stack beams of a different bands?
 
22 ele on 432
20 ele on 220
17 ele on 144
 6 ele on 50
 3 ele on HF triband 10-15-20
 
Also have a 55 ele loop on 1296.
 
Was thinking about putting the 1296 on top, but got a suggestion to put it  
in between the HF and 6.
 
Half wavelength apart on 144, 220 and 432 is no problem.
But a half on 6 and hf is too much.
I was hoping 5' between HF and 6
5' between 6 and 144
then half wavelength of the lower band on the rest.
Comments?