If I had your options to consider, I'd keep the $$ from the second
tower, put some of it into a Tic-Ring Rotator for the lower Yagi, and join
in the fun on the air.
If this thing is to be done a budget, let's not forget swing arms and simple
J-arms that allow rotation around 310 degrees This is a very viable option
when using tribanders or monobanders I have been using HD 73 rotors that can
be picked up for as little as 50-75 bucks at a hamfest for this purpose. The
mounting plate and angle pieces can be fabricated for even less.
Although the rings have a good rep, this method has worked for me for almost