12 sounds ok. 84 holes, not so much.
yeah, no kidding
i did find another solution, 12 bolts, 4 holes per set on the back ring = 48 threaded holes, 3 holes per set on the front plate = 36 thru holes and based on the angles in each set i can get the following clocking options (0 degrees is the default clocking of course)
0,1,3,6,9,12,13,15,19,21,24,25,30,31 (and so on, didn't calculate past that as it would be past horizontal)
or
0,1,4,6,10,12,13,16,19,22,24,25,30,31
or
0,1,5,6,11,12,13,17,19,23,24,25,30,31
or
0,3,4,6,10,12,15,16,21,22,24,27,30
and so on, all based on how many degrees the front plate holes are spaced at
but unlikely i will drill that many holes - i will measure the current angle and plan to be somewhere 1/2 way to the horizontal so i won't hit the floor/tub and call it a day.
only problem i'm having now is if i can machine that pipe on my lathe, it is very close to its max capacity and i need to get my 8'' chuck fitted to the spindle to be able to clamp it.