How will he get bore wash its not like its throwin in way to much fuel so its chuckin out black smoke, all it is doin is tellin the e.c.u to basically keep the choke on, another friend of ours (the reason why he decided to get 1 of these resistor thing) has had 1 on his cougar for well over 2 years and he's never had any problems, if it was overfueling to the extent to cause damage from experience i would expect it to keep killin spark plugs.
If it does blow up just mean some extra cash 4 me 2 fix it 4 him lol =D