Transmission 1 is a GM corporate transmission also known as a SM318 and with an OD it was known as a SM319. The OD part was BW, but the front part was GM.
Transmission 2 is referred to as a SM 320. It could either be a BW T85 or a BW T89. The T85 has a 9 bolt transmission with the shift levers being in a straight line. The T89 has a 9 bolt cover with the shift levers staggered. Neither had a synchronized 1st. They saw limited use in GM vehicles, but were used a lot by Chrysler, Ford and AMC. Ford used the BW in their Police Interceptor and they stood up will behind the FE390.
The Saginaw resembles the BW, but it is a GM corporate transmission. It was the Saginaw that first offered a synchronized 1st gear.
