Best spark plugs for my '73 240z?

[Dadsun]

My first Z car, and I've got a list of items to check. This car has been driven very infrequently in the last 17 years, at least. 

I've run it a few 20-40 minute drives after changing oil and air filter and flushing gas tank. It has the flat top carbs. 

If for sure needs the gas tank dropped and restored. It also, on the last go round, after only about 20 minutes, and a gas station stop, idled rough and some brief dieseling. 

I'm sure the carbs need adjusting, but also want to replace the spark plugs. I've heard to get the "colder" running plugs.  Any recommendations on the best set?

Edited April 29, 2020 by Dadsun

[siteunseen]

Plugs are cheap but you may want to address those other problems before wasting the few dollars.

To answer your question ngk bp6es is what's stock or the most used for stock motors.