We have 3 dusters, a 73, 74 and 75. The 75 is a backhalved ladder bar car, but the other 2 are leaf spring cars with the springs moved inward 3" to the frame. We have 28" tire on the 74 but when we put new quarter panels on it we sliced the bottom front edge of the wheel wheel and moved it forward some. The 73 we used to run a 28" tire and it cleared fine from what I remember but we ended up putting a 30" tire on it and had to clearance the front lip some. I'm thinking a 29" tire and stock wheel well is going to be real close it just depends on where the rear end is located. If I were you I'd go ahead and move the front lip now while it's in primer and easier.