TT wall mount height

It doesn't matter, as long as it's convenient for you to use.

One consideration that does matter, though, is what type of wall you are mounting to. Generally speaking, you want to use a masonry wall, which would typically be found along the outside perimeter of most homes.

On these Wall mounts you want it waist hight and be sure you get the 2x4's on each end.You will need a stud finder for this.

I have no trouble finding studs, I need only look in the mirror. Hardy Har Har.

Seriously, though, I have had this mounted before but I am moving into a new house this week. I had it mounted at about shoulder level previously and wondered is there was any "optimal" level, other than for convenience, before drilling and driving the lag bolts again.

You should mount it such that the TT is at a bass null to minimize airborne vibrations.