You would want an AOD from an 86-88 Bronco or F-150 4x4. The AOD from a 302, 351W or 300I-6 will bolt up to your 300I-6 and t-case. You'll want to get the t-case to tranny adapter for the AOD, along with the shifter linkage for your t-case. You may have to modify the t-case shifter linkage from an AOD/B-W 13-56 t-case if you have the B-W 13-45 or NP208. The AOD also uses a T.V. cable, which needs to be properly adjusted for the AOD to shift right. You might find some info on the swap in the link to Miesk5 Homepage in the Tech Articles forum, JSM84