5W30
To gain some elbow room I would remove the distributor. That's how I do that one.
4.5 quarts
I would imagine it is in the oil pan
5 quarts
I have one in my 1988 Chevy K1500 with a 350.
THere is a fill plug located approximately 2\3rd up from bottom. fill differential with Diff oil until level with bottom of the plug.
I use castrol 10-30.and I recommend it.
SAE 5w30 any major brand.
5Qts. with a new filter.
It SHOULD be 5 unless you have an after-market, high capacity oil pan... then you have to go by the manufacturer of the oil pan.
Yes there are oil cooler lines that come off of the oil filter adapter, they feed in to an oil cooler that is built in to the radiator.
Open the hood, climb up into the engine compartment, look way back under the driver's side of the distributor and you may see it with a good drop light.