I've got some surface rust starting on edge my trunk lid and also around the lips of the rear wheel well fenders ....Won't be getting a new paint job (a shop will do it) till after I get a new motor, so it might not be for a year or two....What should I do to prep this area for the time being? . ...car has the original lacquer paint '75 and when I get it painted will probably just sand to original primer and cover with acrylic?...Don't want to go to bare metal as the car is in excellent condition....thanks.

First things first, check really close and make sure you're really seeing "surface rust". rust in these areas is often coming through from behind.

As in... a bunch of crud's sitting in the lip inside the wheelwell, getting and staying wet everytime the car's in the rain. It rusts through the lip on the inner fender and starts attacking the inside of the outer fender... by the time you see it on the outside of the car, there's nothing left but paint.