Just wondering what oil should be used in a 1967 coronet air conditioning with factory twin cylinder pump?

What type of freon?

I'm probably going to use the consumer bottles (6oz) of Red Tek 12a equivalant to 18 oz of R12.
I also have a bottle (4oz) Red Tek oil charge, which says that it has 2 oz of oil lubricant.
Just to make it clear the oil I'm after is for the lower crankcase area of the factory twin cylinder A/C compressor, from the service manual it appears to say that eventually the oil in the lower crankcase gets mixed in with the freon in the whole system, seems like that is a separate area just to lube the bottom end and pistons in the A/C compressor similar to a normal car engine with the lower separate from the top end??

While the crankcase oil does lube the compressor lower end, it also migrates throughout the system before returning to the compressor. Red Tek is (supposedly) compatible with mineral and synthetic (Ester and PAG) oils.

As far as I can remember the factory service manual showed how to make a dipstick. You removed a plug at the rear of the compressor and checked the level. You also added what was needed at the same spot. This took care of the complete system and no other oil is added.

Yes, that's correct about the dipstick to check the refrigerant oil level in the compressor. But, to check the level the system has to be bled down.

Yes, i saw the whole make your dipstick BS in the service manual, shows to make a dipstick for both sides, the sump plug filler hole and the crankcase oil filler hole.
Just want to make sure to put the correct type of oil in the POS, LOL.

Check with Napa. They may still sell the mineral oil for R-12 systems. They came in quart containers.

Mineral oil on ebay.

https://www.ebay.com/i/324138993848...3k9rG6gIVA77ACh2W1wL1EAQYBCABEgKIHPD_BwE

Mineral oil charge can,

https://www.ebay.com/i/333589541920?chn=ps

R-12 mineral oil

http://www.partdeal.com/mei-r12-refrigerant-mineral-oil-quart-8240.html

I still have an unopened 30# cyl.of R12 in my basement.