This setup will give a Bronco a super low 1st gear approximately double that of the stock 3-speed. The NP435 can be found in 67-83 F100-F350. The T18 can be found in 68-82 F100-F250. The trans you select must have a 28 spline output shaft. The new overall length of the NP435 and the adapter will directly replace the original V8 assembly, so no driveshaft modification is necessary. The T18 and adapter are approximately 1” longer than the original V8 assembly so driveshaft mods are necessary. This kit includes a machined aluminum adapter housing, gaskets and bolts. The gearshift handle will have to be rebent to come out under the dash. Mods to the floorboard will also be necessary.