Think Outside the Catalog
You lost me at wanting to keep the carb. I'd go with the full XJ swap, including the ECM.
It's so cool when that happens. I had to replace the heads on my 2001 5.9 Dodge Durango R/T (my fault, bent a valve installing roller rockers). After being down for 10 days, it fired up on the first key twist like it ran 10 minutes ago.Fired right up. Spent a little extra time cleaning parts.
Again thanks for the help