302 motor blows out blue/gray smoke. would that be the valve seals and plus the rear seal leaks oil and it goes through 5 quarts of oil in a day

Burning 5 quarts of oil in one day?! Contact the manufacturer of the spark plugs with that info. They may purchase you a new engine just to get the plugs back to see how they lasted past one day.

If the rear seal is leaking 5 quarts of oil a day and you're burning oil too with the blue/gray smoke then that motor is shot and you either need a complete rebuild on that motor or a replacement motor from a junkyard. Don't drive that car anymore as you are polluting the air we breath and probably blowing oil all over the vehicles behind you on the road. Get a new motor or a new car. Kenny/MrblueOval