5x5 Rear end for 63 Suburban?

[EricU]

So it is finally time to start the build of my ’63 Suburban.

Current plans call for:
Install a rebuilt Caddy 472 street torque motor/TH400 tranny
Air bags front and rear to get it to lay frame on 30” tires w/wide whites on 17” steelies
Front end swap, either GSI or Choppin Block with 5x5” disks
Rear, C-notch and other items from Dead End Garage
Add AC with an under dash old school looking Vintage Air unit
Stereo: Big
Paint and install a 1960 hood that I have for it.

My question is about the rear end. This truck has about 100k +/- (I don’t really remember as I was planning on modding the truck anyways)

* Should I rebuild the stock rear end and convert to 5-lug?
* Is there a bolt in swap? I don’t need steep gears as it will be a cruiser. The Caddy motor has a lot of torque but they don’t like to be spun up.

Thanks, Eric.

PS, if you want to comment something about keeping the truck as is, stock, or “you’re going to ruin it” etc, then well sorry and you just don’t know me.