Couple questions for youÖ
1) when you say semi-permanently mounted, do you mean you want the Starlink dish on your roof, even while driving?
2) do you need to have your router inside?
Iím assuming youíre interested in using dishy mcflatface (gen 2 rectangular dish) as you also mention you wanted to move it if necessary
Thereís a lot of threads on here about it and thereís ways to do it you can find on YouTube, though most of them will involve disabling the motors and then placing the dish in a deep roof mount. Disabling the motors means drilling into your dish to unplug them. Some people drill a hole with a hole saw in the right location, access the motor wires, attach them to a toggle switch that then fits back in the hole. That way they can toggle the motors back on if they need to remove the dish from the roof and gain back full functionality.
Personally, I wanted to keep my warranty and wasnít brave enough to do that. Instead, I added the short wall mount to the roof of my Ventana by affixing it to the metal bracket on the drivers side rear that holds the fake awning cover. The top of the wall mount sits flush with the top of the facade. When we get to a campsite, I climb up the ladder and put the dish in the mount. It has full clearance to rotate and tilt and has worked great.
Iíve also tried flagpole buddy, which works great but I didnít think that would meet your semi-permanent requirement.
Iíve now got a new concept. Iíve purchased another short wall mount and two 2Ē diameter rare earth magnets with m6 studs. Iíve bolted the magnets to the mount through the mounting holes. Each magnet has 24pounds of holding force on 1/8 inch metal plate. Iíve tested the mount with the two magnets with vertical and horizontal pulling force and it holds up to about 55 lbs before I get separation or sliding.
My plan is to now pick whichever six of the metal awning/facade brackets has the clearest view of the sky (front, middle or back, left or right) and stick the mount there - it does mean I still need to climb up a ladder each time, but again, Iíve got no desire to drill into my dish and Iím too cheap to buy the in motion dish for 2500 bucks.
As for cords, Iíve mounted the router in the basement behind the electrical bay. That way I just run the cable through the same grommet as the electrical cord. Iíve had no signal problems inside the RV.
I did make one change to the cable as I donít find the connection ends to be very robust. Iíve left about one foot of cable attached to the dishy end and them cut it. I leave that always plugged into dishy. I then used shielded cat6 terminators with the one twisted pair flipped to align with starlinkís pattern (not standard a or b). I connect those two ends using a waterproof cat6 connector as itís more robust. I still need to coil up the cable and shove it in the electrical bay, but I feel better about the constant disconnecting. Even if the terminator goes bad, it can be replaced rather than starlinkís proprietary end.
I hope you find an approach that works for you! Good luck and share what you end up doing so we can add your solution to the mix!