Never seen an off the shelf solution BUT:
While trying to install a 4.0 EFI system I bridged all my old fuses with steel dowel pins, then potted the old fuse holders with sikaflex silicone sealant, so I was just left with a plain butt ugly bulkhead connector. Nothing to stop you going all Gucci with a multi pin connector from RS or Deutch though.
To protect my vehicle wiring I used the old XJ fuse box mounted from a bracket in the engine compartment, as high as I could get it behind the RH headlamp.
But to be perfectly honest I recon I could nick the Jeep easier now than before, and the fuses are only a couple of inches higher now than they were.
The flip side is that it now uses modern type fuses and I didnt have to splice the 4.0 ECU into ‘77 vintage wiring.
So my real question now would have to be: Why?