Which 1.2 liter engine does your 1/2-ton have? Also, is it a Nissan 720 pickup, or a B122 (imported from Japan)?

The jets for the A-type engines vary every year, even different jets each year for the same engine type, depending on the vehicle model, state, transmission, etc.

The jets you list sound about right. At the end of the
Carb adjustment, troubleshooting, rebuild and inspection article is a list of factory-spec jetting for various a-type engines.

My Datsun 1200 half-tone Pickup, (Make 1993) consumes a lot of fuel.
Average of 8-11km per litre.

I have two problems:

1. I checked the jets and they are:
Idle Jet - 97
Main Jet - 135

From your experience, which combination is the best for economy.
Someone told me 85 and 97 will do.
Another said 80 amd 100 will.

2. The car hesitates whenever I accelarate.
I have cleanup the carburator a number of times in vain.

Please I really need your expertise!