mounting an outboard

[Joker2]

Just finishing up my complete transom rebuildon my 75' V, I set it up for a 25" shaft motor. I was wondering if I should take on the job of mounting the motor ( which I don't have yet ) myself or should I pay someone to do it. I'm not sure how to determin the best height it should be, keep hearing the cavitation plate should be even with the bottom of keel. I also heard it might cavitate around turns this way. Don't know who to listen to. Any thoughts? Thanks