Silversmith It depends on which gasket is used or if any is used. Clean dry surfaces is important. If there is no chance of
oil drops on either surface and the
oil pan is a flat surface, a good stream of RTV of 3/16" around the whole pan area on both side of the bolt holes. Will need 2 small tubes or 1 large tube and a caulk gun. After its applied allow 2-5 minutes depending on temp out side and install onto motor. Bolt inpan with all bolts a couple of threads. This is IMPORTANT go up both sides or down both sides swapping right to left. This will keep the pan and RTV from squeezing out too much. Go back and torque bolts to correct tightness and let this setup for 24-36 hours before installing
oil in the motor. Run the motor for a couple of minutes and turn off. Need a couple of heat cycles to fully cure the RTV. Make sure you don't have any pressure inside the motor, open filler caps, remove breathers, PCV is fine when heat cycling motor. After 2-3 cycles, check for leaks and drive like normal or as you stole it. Put paper or cardboard under car and check for leaks.
If running gaskets, (which I do on the 482 motor) I HI-Tac the cork gasket to the oil pan and let stick and use a thin layer of RTV on the other side. The cork gasket has limiter metal plugs in it to not over tighten the gasket or crush it. I have removed the oil pan every year to check the bottom end of motor for bearing wear and clearance and reinstalled same gasket with thin coat of gray RTV. Going to replaced gasket after 16 years of running the same one. Had a valve cover gasket finally come apart and cause an oil fire in the car. I do push the limit of all my gaskets and seals. If I had the money change the gasket every year. 5-7 years is a safe limit or until you see an oil leak on the ground. Same applies with everything being clean and dry of oil or dirt. Either way, don't be in a hurry. Have seen more failures from driving cars after the RTV is installed trying to rush the curing process and instead having leaks worse than what they started with. Best Seal is Gray, GM, FORD, Dodge all sell the same thing. We got the good stuff from Honda.
Warm weather is coming. One side note measure the oil pick and check this with the oil pan to make sure you have the correct hieght and clearance for oil pickup. IF the pickup is too low you may starve the oil pump for pickup and cause air to get into the oil. Pickup too low, have seen them wear a hole in bottom of cheap oil pans, or break the screen in the pickup and any jun k in the bottom of the pan ends up into the oil pump and motor. Guys are lucky if the junk just breaks the pin for the distributor and saves the motor. I saw one 30K motor loose a roller rocker and all the little bearing when into the oil and through. Owner got lucky. Complete rebuild with gaskets and seals. Rick L.