Need help w/gear and slick size on a 402 Duster

Putting together a 70 Duster, it was a 340 car. 402 Magnum Stroker Crate Motor, Dist. and Orange box came with it. Have S.S. Springs, stock 727 w/ 2800 TCI 11" Breakaway , TTI step Header w/ 2 1/2 " full exh. ,750 3310 Holley . Can always up grade the carb., convertor, and go to 3" Exh.. Conservative set up, but I like what I have, just starting out. Still need things like a shift light and rev. limiter. Only had it out once and got rained out. Got one good run in, but it was in Drive so it shifted early. I plan on shifting @5500. Since then, I've added frame connectors, a driveshaft loop, and got rid of the power steering. W/stock 25" tires and 3.23 gears w/ sure grip---rolled and stomped it. 13.232 at 106. Don't know what to do about tire size and a gear. Will I need a tall tire with a stroker? I don't have much experience with Drag Racing, and I'm asking You Guys to fill in the Blanks. I'd like to have a respectable MOPAR. Any and all suggestions would be appreciated. Thank you for the A-Bodies Web sight. :cheers: