v8 swap and lift questions

[the99camaro]

I'm currently in the middle of swapping a c4 and a 302 into an 88 bronco 2. Also has been lifted 4 inches. My question is the stock rear drive shaft in an 88 looks really weak like a tooth pick so I was at the junk yard today and stole a manual t case from an 84 b2 and also took the drive shafts because they were attached and the guy gave me a package deal of a $100. They are huge compared to mine so I thought they would be an upgrade I was just wondering if I could use them the way they are or am I going to be looking at shorting the rear. The c4 that I have I got at a junkyard it came with an advance adapters on it for the transfer case for this swap but I know they have 3 different lengths does anyone know off hand which length is for the stock c5 and manual t-case to keep them in stock location. The way it looks now just eye balling it I have the rear drive shaft from the 84 hooked to the manual transfer case and have it in the b2 it looks like it is to far forward and that I'm going to have issues when I put the trans and engine in. Let me know if you have any suggestions thanks. I will try and clarify anything if none of that made sense.