found tag on the c4 what is it

here's the numbers PEE V1 DOOPD M4, thanks Mike

You have one of those weird 1970 transitional transmissions - Early 8 bolt valve body with late spool type manual valve in it - 1970 only 26x26 spline input - 1970 only forward drum.

And your DOOPD (Dee-Oh-Oh-Pee-Dee) is really D0OP-D (Dee-Zero-Oh-Pee-Dee) which will work a lot better when you search for information using a search engine.

I am not near my codebook so I can't tell you exactly which vehicle this fits other than it came behind a larger motor, probably 302V8, in a mid-sized car.

It as the '70 Falcon that had the odd 8-bolt valve body. All others apparently had the standard '70-'73 9-bolt type. If yours uses 9 bolts to hold the VB on, you can use the standard shift kits and stuff. The 26x26 input is not an issue if you don't have to replace the forwrd drum or want to install an aftermarket input shaft over 600ish HP. In either of those cases, you would likely change to the '71-up 26x24 input and drum as a pair. Otherwise it's a good base to build on.

David