6l90e or 4l80e?

[l92powered77]

I have a 2008 L92 and 6l80e in my 77 its not running yet.But i did have to take the tcm out and send it to PSIconversion.com so they could flash them e38 ecm and tcm together.Im in california and not in texas right now and dont know anybody who tunes good out here so thats route i took.I couldnt pass up the opportunity to have a 6l80e in a old school chevy;not too many people have a 6 speed auto ls swap in a old school.