Center Section Differential Recommendation

Please bare with me, I'm not knowledgeable with these things which is why I'm posting this thread.

I'm replacing the rear suspension on my 72 Demon that currently has the full RMS front end, 360 and 727 column auto. I've ordered and received the RMS Street Lynx with 8 3/4 Housing & Axle Package stock width 30 spline. I was informed that I still needed to purchase a center section differential to complete my parts list before installing, minus a custom shaft that I guess I'll just have to go over once the shop installs.

The end goal of the car will have a gen 3 hemi 392 with on the floor stick shift but that wont be for quite some time so whatever I'll put in the rear now, will preferably work with both or at least with the least amount of modification/parts once I'm ready for the modern stuff.

Can anyone please recommend me to purchase a center section that they feel should work with what I have currently and hopefully what I'll have in the future. Any insight is appreciate and sorry for being a noob and asking. Thanks in advance.