how many hours on the truck? since travel is so expensive, it would make the next trip with enough new coils and spark plug wire assemblies to replace them all, and replace the wire harness to the cam and crank sensors and gap the plugs to the correct gap.
it is possible that you -do- have a failing cam sensor or crank sensor too. I strongly suggest you get OEM or 'known good" (from a running k21-k25 motor for testing) ones.

I have a customer that has a Nissan mpl02a25lv. CODE 27. I didn't have the correct OEM Shorter spark plugs. the plugs that was removed had a gap of.40 bad plugs. installed Autolite. SPARK PLUGS. And found #2 coil bad. So I ordered the correct OEM SPARK plugs, And a new coil. coil arrived 1st. installed ran a little better but still had rough idle and miss. Installed OEM plugs. forklift ran like a champ for 2 days. then code 27 is back.? Any ideas. Maybe check each coil. what a headache customer is 120 miles each way. PLEASE HELP.

I agree with edward change your plugs. Still giving a fit the unplug each coil pack while running and listen for change to narrow down possible coil pack that went south. Being an L02 you might have joy joy on plug removal.

replace all the spark plugs with the OEM (please do not use aftermarket will-fits for these) and any coil packs and spark plug wires that seem damaged from not changing the plugs in such a log time.
this code is generated when the electrodes on the spark plugs have worn excessively.