[BillyShope]

As a fellow geek, I had to play with this for a while. I derived the velocity as a function of angle and rotational speed and verified your answer for 6.16 and 8000. (Actually, I got 8763, but I won't quibble.) I then calculated the location of the instant center and, using velocity vectors, got the same answer. I then used ViaCAD for a graphical solution and, again, got the same answer.

I wanted to take the relationship for velocity and differentiate with respect to angle, set equal to zero, and find the maximum velocity angle. This turns into an algebraic nightmare, however, so, at that point, I resorted to the spreadsheet to find it.

Fun to do this sort of thing once in a while. Keeps my septuagenarian brain active.