Novak 5mm Replacement rotor

[JThiessen]

I think I have another issue with one of my 4.5's. Last fall I bent the rotor on my HV-4.5 in my Maxx. So a couple weeks ago I ordered a replacement 5mm rotor for it. When I installed it, I had a heck of a time getting the end of it to go into the bushing at the back of the motor (it actually hit the circuit board fairly hard a couple times). I thought this was a little odd at the time - seemed way too sloppy to me (I thought the fit would have been tighter through the windings). Over the last couple weeks, I transferred everything over to my G-Maxx chassis, and made complete mess out of the garage. SO last night while I was cleaning things up, I tried to put the old rotor into the sleeve the new one came in, and it wouldn't fit. I think they sent me a mislabeled rotor. I dont think this is that bad in itself, but now I'm a little concerned about what kind of damage I may have done to the sensor board in the motor when I was installing it.
Has anyone replaced their rotors? If so, do you still have the old one(s) and can measure the dia of them? Is the 6.5 a smaller diameter?