hello all just bought a.....

i am new to mopar muscle just not new to mopar....04 1-ton dually and 09 caliber for the wife.... i might need some advice with a rear end..,, ok my demon originally came with a slant 6 and 3 speed with a 7 1/4 rear end and now the demon has the 340 from a 71 and a 727 with the same rear end....i have a guy here that has an 8 3/4 rear end but its been modified so you can put slicks on it....very short axle and long spindles am i gonna have any problems bolting that in and the tires have to be about 1 ft across so am i gonna have to cut the inner fenders