Carb is quite crusty (outside). I have always used a carb cleaner, but on further thouht I wondered if carb spray would be damaging to the choke and throttle plates. Being that it is formulated to remove all forms of oil and grease it would leave an absolute dry shaft to rotate - would this cause unwanted wear? Should I try a soap, like maybe a dish soap?. Any thoughts are suggestions? The stock carb functions well and I would like to retain it.

Commercial carb cleaner has lubricants in it. In fact it is not designed to remove all forms of grease, there are instead Degreaser formulas for that.

Go crazy with the carb cleaner. I follow it off with starting fluid (ether) to get it extra clean. Just be careful with ether around the shafts and other moving bits as it will strip the oil.

Your Datsun will thank you.

I'll second carb cleaner rinse, gets all the grime off and won't harm it. I often use it to clean off stuff on my vintage motocross bike (as you can imagine the old 2-stroke builds up a cakey crud in spots)

Tom

Excellant! I will have a field day untill my carby shines like the sun!!!