so i've searched, and haven't found anything yet. looking at a 1994 4l80 2wd, with a bolt on yoke. I know i can machine my th400 adapter to fit, but can I trim the output to fit my 208, or will I have to put a different output in the trans? thanks.

If I am not mistaken, what you should have is a 4L80E. This will not allow you to run the 208 because you will need the electronic speedo to make the tranny shift.