Several years ago a friend in Virginia City sold a '41 four door that I had asked him about many times. When he told me he had sold it to someone else he apologized saying"...I'm sorry but he offered $800 and I knew you wouldn't pay that." The car was perfect. It had never spent a night outside in it's life. My fault for not making a hard offer. I was trying to not pay $8,000.
Borg Warner over drives are great for street driven cars. But like Don says you need ALL of the parts. The Saginaw 3 speed has a one off solenoid that is hard to find and pricey when you do find one. Never throw away a broken Saginaw 3 speed OD solenoid or pass a cheap one up. They can be fixed. Also if you do a conversion like his you'll have to have the main shaft from the donor trans because the OD shaft is not the same as the standard shaft.