Looking for feedback on tires & backspacing question?

I have a 289 65 coupe which I have done the Granada swap on (8 in. rearend). Also I have some 15 x 7 rims with 4.25 in. backspacing. Looking to put some 225/60/15's on these rims. I'm sure lots of you guys have a similar set-up? My main question is, am I going to have any problems with tires rubbing? Will I have to use wheel spacers? Finally if I have to use spacers; I was talking to a tire guy and he didn't recommend the use of spacers. Because in his opinion you would never be able to get them centered properly and they would cause vibration? Any opinions/ insight is welcome. Thanks in advance

Maybe the tire guy was trying to sell me new rims for a good commision? He wasn't anybody I new or trusted. My car was just converted from a 6 cylinder drive train to a V8 rearend and drivetrain that is why I am gathering info. because in this case the old rims definately won't work. Sorry, I should have mentioned that in the first post. Also I came across these rims by chance and am trying to find out if I can make them work for now (no they are not hot). I may not keep them forever but can't afford to shell out the cash for a new set of Torq thrusts right now. I have been doing some research and 3.75-4.00 in. Backspacing seems to be the recommended size. Thanks for your reply.