what is the widest rim u can get on the rear of a 63 dart

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I have 7" wide with 4" backspace on my 66 Dart. 225/70-15's with no trimming or rubbing. I think 8 wide would fit but wheel lip trimming or rolling is necessary.
Hey Mike, I'm thinking about putting 15x7 sbp Cragars on the back of the new D/Dart. It seems your rims are neutral offset (centered in rim barrel). How much more tire could you stick under it? On the other D/Dart, I had problems with the leaf spring clamp on the pasender side. Those were 15x6's with a neutral offset and 28.0/9.0 15 - M/T ET Drags. I have SS springs on it so it clears the sidewall. So more tire?