Don't want the slab tab obscuring the mintmark on my favorite RPM Buffalo nickel

Have owned this one for years and taking advantage of the quarterly special to crack it out of the old green PCI where it was labelled as a simple D/D and get it properly attributed as an FS-502. My concern is the lowest of the 4 Ds is very close to the rim , where it would likely be at least partly blocked if the 3-tab insert is installed in the orientation I have usually seen, with the lowest tab at 6 o'clock. I guess I could ask for a reverse mounting, but I really like the obverse toning and prefer it be slabbed that way.
Customer service rep said writing a note on the submission sheet would get the correct result, but I'd like to make sure. Anybody else deal with a similar issue?