11" Rear and 9" front widths are common for stock bodied Pantera's. The 11" wide rim would be the minium required for the 335/35 tire. On my '74 I have that exctly that with 245/40's on the front rims. I think you can go to a 255 width front, but they'll likely scrub the inner fender on tight lock.
Of all importance here is 'offset' a subjst which has been discussed numerous times on the board and you can do a search if you need more on that. Buying from a Pantera vendor will get you some nice wheels designed for a Pantera with correct 'offsets'.
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