the junction block is no big deal. Hell, the factory TJ one may work, otherwise it's $20 at the parts store.
He'll need the spicer 2-2-1379 flange adapter to go from 8.8 flange to the 1310 joint, and it's very likely that he'll need the shaft shortened by about 2 inches if he's not lifting it at the same time.
The 8.8 pinion is quite a bit longer than d35, and then you've got the extra 1/2 of the flange adapter as well.
It's gonna make the driveshaft on a stock height TJ super short. It's gona vibe. Since you're having a shaft made it may be wise to rock a hack n tap or short shaft kit and go full CV shaft. might find a stock front that will work.