[TowerTalk] Two towers

[W R CUNNINGHAM]

Good day gentlemen, I need some advice.
There are two hams in this household, myself and my 13 year old son Sean, ke7cws, and we have some questions.
We currently have two towers up; one is about 45 ' and has a large 6 meter beam at that height and a small 2 meter beam about 10' feet above on the mast. About 75' due west of that we have a 55' tower with a KLM kt34xa beam just above the tower and a 12/17 meter beam 10' feet above that. The system works very well as is.
My son was given his own transceiver by a generous gentleman and has it in his bedroom. hooked up to a fan dipole hanging off of the 55' tower. It runs through a tuner and works OK. He would like to have his own beam.

In the process of searching for a 40 meter rotatable di-pole, I have run across a  Force C4E beam, 10 thru 40, and would like to use the 40 meter dipole off of it above the KLM and move the 12/17 beam to the top of smaller tower. We would then be left with a tri-band beam that we could mount in place of the 6 meter beam and were wondering if there is enough distance between the two towers to be able to handle two tri-band beams. We would not operate them at the same time but would like to know if they would interfere with one another or if there would be any problems or considerations we should know about. 

We thank you in advance for any help you can provide. We've been having a ball and it's a great hobby to do together.

Thanks, 
Ron and Sean
W7CWR /KE7CWS