Take the overdrive apart and just look it over. At that mileage you may catch things getting ready to fail. Just behind the OD clutch you will find a wavy snap ring setting against the flat snap ring. Replace that wavy snap ring - very high failure rate. The OD clutch is the first clutch you see when you pull the OD unit off the trans. All the needle bearings - check them all real good especiallly the one on top of the unit when you pull the OD from the trans. Make sure you do not drop that bearing - you will fracture the race and it will fail later. There also is a thick shim under that bearing that sets on the OD piston. Make sure you don't lose that. Keep everything in order as you take it apart and you should have no problems putting it back together. The only other item that takes a hit is the small and large bushings in the output shaft. Check those out reall good too.

Save your money - you don't need anything more than a 3.8 lever and the standard strut and anchor are more than adequate for even a race trans. The 318 converter will probably stall in the high 2's low 3's with that torque.