I have made TWO upgrades to my Sensar III one by choice. one by "Opps"
First I do not have a wall plate but a box of many buttons (Matrix Swtich) still I will assume you have a wall plate.. I replaced it with teh SENSAR PRO (About 100 bucks when I did it) direct replacement save that there is no "Front" antenna connection.. You may have to file a small notch to bring the TV-1 lead from the back to the front so you can connect to it if needed..... Big improvement. This is a multi-function device, it duplicates all the functions of the wall plate but adds additional adjustable amplification and several other features.
Then (Opps) I forgot to crank it down so a handy dandy tree took care of the Sensar III head.. The lift ares were NOT damaged so I ordered a new head, about 50 bucks. Sensar IV.. That is currently the best RV antenna made for RVs (There are better antennas but not made for RVs).. Replacement was two pins and one coax connection.. Pair of needle nose pliers is useful or a pocket "Multi Tool? type knife. That's all.