You might need to make a few adaptions to use this one but... (And there are others you might not) this is a 2-hole mount You may wish to turn it upside down. and you may or not need to cross the hot and cold lines you night also wish to add a vacuum breaker (Any RV store should have one in the proper size.. 1/2") but.. It has a significant advantage.
It was widely discussed in these forums a few years back.
Thermostatic valve on AmazonIt does the best it can to deliver a consistent shower temperature so long as you don't run out of hot water.