Help with an 8 3/4 swap

I just replaced the 7 1/4 rear end in my 68 dart with a 8 3/4 from a 65 coronet. It has already been shortened to size, but im not sure if the drive shaft will need to be shortened. I have the rear end in, but not bolted down, and it seems like the drive shaft is only off by about 1/4 in, i figured if i tightened it down it would fit, but after some research it doesnt seem like it will.
Does anyone know for sure? if so, how much would i need to cut off?

All help is appreciated!