You will have to take the transmission pan off and change the filter inside. Make sure you remove the old gasket as well and put a good new one on. Use silicon sealer. Ultra Blue is good. Top with new trans fluid till it shows level on trans dipstick (while engine is running)
motor oil, transmission fluid, rearend grease, power steering fluid, and brake fluid.
Neither is the plug you are looking for. On a GM transmission you need to drop the pan to change the fluid. May as well change the filter while you are in there and sue some kind of silicon sealer when you put it back together or it will leak for sure.
The transmission fluid capacity of a 1974 Chevy Nova is 10 quarts. This includes a large amount of fluid which is stored in the transmission and torque converter which is never fully drained.
You add it through the tranny dipstick hole, pull the dipstick out and add the fluid.
ANOTHER ANSWER Technically, your 68 Nova Automatic Transmission was designed to use Dexron II transmission fluid. It's called a "friction modified" transmission fluid, meaning that it was designed to work with the internal clutches. As friction modified fluids are all slightly different, it might be best to stay with the stuff that was originally designed for the transmission, but you might be able to get more information from your locak transmission shop. ANSWER Any fluid that says dexron on it.
passenger side, right behind headlight
Between 12 and 13 qts. if completely empty.
The easiest way is to drop the car off at a local transmission shop, give them eight hundred dollars and your phone number. If you really need to ask this question the job is over your head.
Answerapprox. 8 quarts (plus shipping and handling)
MANUAL 80 90W AUTO DEXTRON 111
If it's a turbo 350 it takes between 12 and 13 qts. to fill completely.
You can get a filter kit from most auto supply stores. Drop the pan, drain the fluid, (this is a good time to add a drain plug kit) clean the pan, change the filter, reinstall the pan with new gasket, refill.