Winter transmission builds

I am planning to build my 727 after I get a few more parts. I'll be asking for some advice on some of the stuff... clearances and what to look for. I have 2 good 727s to build im leaning towards the non lock up hd 78 truck trans & 2 was in a 10 second B-body no billet drum but I'd like to see whats in it.
Get a billet drum. Your right pinky toe will thank you later lol