Does anyone know off the top of their heads what a bolt pattern for a manual trany bellhousing in a truck is? Is that a Borg and Warner 4 speed, or a New Process?

cant remember

they were all NP435's I do believe from 62 to 93 I think

All the ones I've seen had 2 bolt patterns. 435 was one, I assume that the car 3 speed or 4 speed was the other pattern.

I just see American powertrain is selling one with multi square patterns on it and was curious if that one was the same.

I do not know about the Bellhousing you mentioned. Can you post a link to it?

Regarding factory bellhousings, there were also so a few big block to 833 OD transmission bellhousings. I think the overdrive was only available for a short time behind the 400 engine.

The bell in my truck is a #272 which is the NP435 bolt pattern, 5.125" retainer opening.

There is a #670 bellhousing out there that came behind big block trucks in 77'-78'. There were no factory BB truck/833 combos to my knowledge but for whatever reason the bells were drilled for both the 833 and NP435.

I search daily for a #670 BB dual bolt pattern bellhousing. Not many out there.

Was wondering the same thing about the American Powertrain bell. If you use that I guess you are using a hydraulic clutch setup?