If you only drop one tooth in the front, you shouldn't have to replace the chain (won't need more links). If you only go up three teeth in the rear (which is the same as dropping one tooth in the front) you will more than likely need a longer chain. Like PatMack said, unless you're trying to get into stunting, dropping one in the front AND adding 3 teeth in the rear is a HUGE gearing change. I'd start with just adding a one tooth smaller countershaft sprocket up front (won't have to replace the chain) and see how you like it. If you decide you want more, then buy a new (longer) chain and larger rear sprocket.
Added 64 teeth to the rear!!?? That's like a 110 tooth rear sprocket or so..damn near as big as the wheel! Why in the world would he do something like that? That pretty much makes the bike useless and unrideable!