2.6s were carbed- with a Mikuni at least in later years. (Not sure who made earlier.)

Don't know about EFI on 2.6 in OZ. HP of 131 sounds reasonable for that if it exists. OZ did get a 2.0 with (pretty sure) EFI on the Starions back in the day when US had 2.6 EFIs.

The US SWBs running around with EFI are pretty much those with the SQ turbo swap. Then on top of that a few have gone MPI.

Many here go with Clearwater for replacement. Not sure on emissions part. For mine in Ohio I passed fine. The jets have more to do with early/cold running I think?

Fel-Pro turbo block gasket is highly recommended even for NA motor.