Tom, that's my own fault.
I got inpatient and instead of starting it by hand to ensure that it was good, I used the drill and it drifted.
I rimmed the offending hole with 0.030" styrene and I'll sand it flat with the others once I'm sure it's cured.
Still bummed... but that's what filler is for.
As for the fan diameter, I'll have I check my CAD files, as I don't think I made them large enough from my initial measurements.
Oh, and as for the lip, subsequent inspection shows that there wasn't any that was on top of the carbody. So flush it is...
thanks,
-Mario