whats up guys i can sure use some advice right now,so any and all help is appreciated im workin on my 1981 gmc sierra grande 2500,when i bought the truck it had a 350 and th350 tranny.im buildin it for as a daily driver and as my tow vehicle so i went with a 454 bbc and a th400 tranny ,so everything is gettin changed and thats where i need the help guys .first the engine what needs to be done to mount it any electrical need to be installed changed etc ,oh yeah the 454 is a 1985.how about the tranny what needs to be done the one that came out had the 9"piece on the end and i have a 2 piece driveshaft ,the new tranny needs to be ordered ,the engine is being rebuilt as we speak all replies appreciated