The FAA system (maintenance) system is FAR easier to understand and keep on top of. Unlike JAR/EARSEA...For example we have just spent ANOTHER month grounded due to EASA paperwork. We brought our annual forward 6 months so that it could be done in the winter, and allow unbroken flying in the summer...EXCEPT...you can't bring the ARC renewal forward 6 months (god knows why), only 3 I believe, so now it is out of step with our annual.
So in the middle of the summer the ARC renewal is due which should go straight through (£700 worth of paperwork) but they find an "issue" with the mags. The Mags had a 500 hr overhaul last annual, when in fact they should have had a somethingother overhaul (don't ask me, it is not much different though). So the result is the ARC paperwork can't be completed and we can't fly until the mags are overhauled AGAIN. Does my f***ing head in sometimes. It is a full time job keeping on top of EASA paperwork (and hence probably the £700 ARC RF).
But anyway, back to the original question - If the aeroplane was originally N registered and currently on G then the process is quite straight forward. Ours wasn't originally N reg, but was exported straight to Switzerland and then onto the UK a year later, so it is a little more complicated. Our FAA IA has it in hand though and I'll let you know how smoothly it went (or not) soon!
Good luck!!