That's only the correct answer if the HO knows what height they want it. Most I've dealt with don't have a clue.The correct answer is: what ever height the customer wants it at.
Let me guess he got mad at the plumber and there was battle over payment or, he was calling you back wanting it fixed for free..you probably are going to want a 3/4" hot and cold service to the shower as well. Also check the trap size. I just installed a 12 spray shower stall, homeowner insisted on keeping his 1 1/2" trap... you can guess what happened..