Wireless Joint

I have played with a setup like the one you are proposing. I also tried a small mimo antenna and placing it right under the wireless broadcast panel.

I can give as much detail as you like but the short answer is 2 cheap yagi antrennas and some lmr400 cable converted into smc and feeding the router ...

Additionally - Boosters amplify everything, which includes signal noise which in my experience causes an erratic/less consistent data connection. There are high end boosters (3k plus) that have noise filters, but have never tested one.

So looking at tmobile (see it on B4 and B71 using a crapo app) now, got verizon up and going. I see ATT also. (B2)

So for Tmobile or ATT, it is going to take some elevation but possible. I have a 60ft antenna break over mast. So I can achieve this. My concerns are antenna selection, also where in ...

Would try to move your setup 0.0 miles from the tower to test to make sure
the problem is the signal and not the modem or SIM

I agree. I need to start with a basic setup and sim. See where that takes me before going all out.

I do have ec25-af, ep06-a and 7455. Two spitz to test on. Yagis with be here Tuesday and I can start basic band 2 and 4 testing.

Should grab a USB to pcie... have several old routers with USB laying ...

Sure, Just keep in mind I am like the poster child for worst case scenerios to get good signal. I have mountains and thick trees and my closest tower line of sight is about 10 miles away. Before all this it was difficult to even make a good phone call.

With the booster setup I would get anywhere up ...

I have that Netgear mimo antenna sitting in drawer presently unused. Used it for about a year with my Netgear LB1120 before my present setup. It gives a very small boost to signal and is in my opinion not worth the money. Which at that Amazon link Dr-BroadBand gave I notice is much more than I paid ...

What you really need to ask yourself is
do I really want to mount and AIM 4 seperate antennas?
or
get a single device that needs aiming?

I have clean line of sight to a Verizon tower with only B13 about 10 miles from my house with no other towers available. I can pull it in, but the signal is not great even with a 7-10dB MIMO panel antenna. With RSRQ around -11 and SINR about 8 I can get around 3 megs down and 8 up on a good day ...