The MC 21XX series need an adapter (Gronk's looks to be about perfect for that)
You can run an older BBD Carter. They were also used on Dodge 318s and slant sixes.
Webber 32/36 or 34/36 (I think) bolts in place of the BBD but needs linkage mods. If you search Jeep 258 carburetor, you will find all sorts of stuff. I fix all the BBDs and so far only found one that was TOTALLY dead out of a few hundred. I thought about rebuilding them for a living, but they are nearly gone and the way shipping companies and USPS handle stuff (drop kicking it into the bins and playing football!) they get messed up pretty quick.
I'll stick with converting to EFI with Jeep parts, thanks! In springtime, after I sell my Comanche (going up for sale seriously in Jan) I'm going to get the parts together from my collection and put an AW4 in my Eagle wagon with NV242 (just bought a '93 Grand Cherokee with parts 4.0L and NV242 for $500 with brand new tires I put on the Comanche) Once the Honcho is drivable, I'll do the swap.
I have a complete '91 XJ HO efi harness to put in.