So, go back to what worked...
Pulling in the Fox station in KC was always an issue, from time to time. Now just more so... I was "thinking" the 91XG might have more distance & gain on it. Also with the hail damage it is a tad unknown. But other than all the climbing cutting another piece of cable and just stringing through a window and up to the top antenna should not be that bad. I will need for wind and temps to cooperate for that test. Hopefully later this week.
If it still works well, let's build from that. If not, determine if the antenna is in trouble, or the coax, or connectors, etc. (Rubber boots make great funnels to pour water into the coax. And compression connectors are vastly superior to crimp type.) Have you done this test?
http://forum.tvfool.com/showthread.php?t=13646
I have not performed that test. Again, this should be straight forward other than climbing. Changing to compression is easy enough. I'm a tad confused on the pre-amp idea. But listening. So on leads >50' with problematic signals they are of little or no use?
A broadband splitter/combiner is quite unlikely to work in this application. At a minimum, passive filter type combiners need to be considered. Tinlee.com AC-7 for example.
Some brain fog starting to clear will have to investigate those and get my head wrapped around them. Also seems that coax needs to be same length from both antennas before connecting? Maybe I am mixing concepts here.
If you prove the Winegard(s) bad, then yes, the Antennacraft Y10713 is the top consumer grade H-VHF option. (The 91XG + Y10713 make the top of the list for consumer grade deep-fringe/DXing off the shelf options.)
I'm not saying the Winegard on the upper is bad, just now I know I am at the outer limits and KC is UHF only, so why not go with the better item and the price is very reasonable. If I can dial it back in strong, then going with VHF only the other direction would be much easier to combine with the UVSF or whatever it is. That sounds far more workable.
Once you have a west antenna working, and an east antenna producing reliable reception, then we can talk about amplifiers and combiners.
Good points, West is where I am going to begin.
(You may also want to consider a few alternative options such as a PVR/DVR that can be moved or one that has detachable media (hard-drive).