I am pretty sure that most of the 17's on 1500's except for the plain steel ones are all 17x8... And if I remember correctly the HD's are the same.. I would have to go outside to double check on that.

Edit: Just checked and apparently the HD's are 17x7.5

 

yea i don't have stock rims mine are 17x9 with +10 off set

 

Most tires want something with a minimum with of 8 inches.. the stock 1500 17 inch rims are 17x8... It shouldnt be a problem running 35's..

Edit: Running a 10 inch wide rim on a 35x12.50 would risk chances of popping beads if you run hard off road.. it can be done but the 8 inch wide rim is what most prefer.

 

So..would I be better off with a 315/70/17 instead of a true 35x12.50? I think the 315 is a tad smaller.

 

id go with the 35's , why not if you can fit them. mileage will suffer to a degree but thats to be expected