as far as the function of the 70 vs 71-4 E body shifter, they're the same (70 will have the added function of the interlock linkage, but that poses no issue in the tranny swap), the transmission will work with either year set up, there are some subtle differences in the mechanical parts between the years, but for the most part the bell crank linkage will bolt right on, one thing to check is that the transmission has the 2 hole ear tab provision located between the tranny's pan and tailshaft rubber mount (pic below) for the torque shaft bracket, 70 and up trannys should/will have it...if you don't have the boss, you'll have to fabricate something to locate the shifter bellcrank rod, do you currently have a 904 and are swapping in a 904?


One issue will be the manual valve, most are reverse pattern, so now DRIVE(D) will be 1st gear, 2nd will stay 2nd, LOW will now be 3rd regarding the shifter orientation....unless the MVB is standard/stock pattern, which is rarely the case