For warranty repairs, we have to use SBD, (syptom based diagnostics), basically, we login to Ford after connecting the vehicle to ids, select the fault symptoms from a series of drop down boxes, i.e, non start etc. and it then searches Fords database for known concerns and diagnostic routines, I would imagine it would just store various pats fault codes, they wouldn't be able to tell if you'd altered the speed limiter. You could always clear the codes after you'd done it, then try to start it a few times, that way it should just have the pats fault codes stored.

Karl