I rotated the one on my C.It comes off the flywheel very easily using the oven method.You should have seen the look on my wifes face,when I put it in her new oven!Anyway,you only want it in there long enough to heat the ringgear and not the flywheel.After I got it off, I cleaned up the bad spots with my Dremel tool.
I rotated it quarter turn and put it back on using the oven again,just the gear not the flywheel.
You don,t have to worry about measuring anything ,it only goes on so far and thats it.
Make sure you pry it off straight and even.
Mine engages perfect every time,don,t forget to lube the bendix while its out in the open.
Good luck ,Dave