There used to be a 3.4 crate motor GM sold for S10 and camaro owners, sadly no longer available. You might find a used motor out of one of those but the best bet is the 93-95 camaro or firebird.
The 2.8 has a bad reputation, and I agree it's under powered, the edelbrock intake and new carburetor help out a lot.
Personally my 2.8 went through hell and never quit, I've heard other stories of the same longevity.
The Weber DGES 38 kit is a good choice if you keep the OEM intake. If you do get this kit keep in mind the adapter is designed for the s10 engine bay so the bolt used for threading to secure the air intake need be shortened for the jeep
Edelbrock intake # 3785
Edelbrock 3787
Adapter plate can be used with Weber carburetor and I suppose Holley and OEM
Edelbrock 3789
Is the adapter for the 4 barrel Holley carburetor 8007 390 cfm
A few XJers have used the 93-5 Camaro/firebird ecu, intake, injectors and wiring harness.
Basically a good 3.4 with nothing else done , besides for needed to adapt it, will be a good choice to get on the road again.
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