Need help with getting one piece drive shaft in LWB

[sam's 72]

I have my truck over at a friend of mine tranny shop, we are putting in a built up 700r4 in it. I want to go with a one piece drive shaft, he calls me today and tells me that he dont think it is a good ideal to cut out the loop that the drive shaft is going through to get the one piece drive shaft in. The rear trailing arms are conected to this. what I want to know is who has done this conversion? And is there any trouble with cutting out the loop to get the single piece shaft in the truck? I know a lot of you guys have done this, what did you do? did you box it back in, or just left it cut out?
Sam