As per my reply, I would try it first on one set, loosly attached before you do a final installation.
Also I have an omni-directional antenna on my web site,
www.tripleplayantenna.com. I would be glad to send it to you to try before you purchase. If that works, just install it above the roof and use the Channel Master 3418 distribution amplifier.
I feel that at your location, an omni-directional antenna is your best choice for a non-rotating antenna system.