LUVTruck.com

are there 78 luv owners who could give any tips on replacing the ignition coil on a 4 cylinder engine, or better yet, problems associated with a need to replace the coil?

you can get coils at just about any parts store. its a pretty generic design so the should have O.E. style replacement or "performance" one from accel, msd, etc. If you have an inline spark checker you could find out if its something else after the coil i.e. cap rotor points plugs or wires.
you can get spark checkers at auto parts stores or harbor freight for under 10 bucks. definitely a useful tool that is simple and will help you with almost anything with a spark ignition. from lawn mowers to cars and everything between.
i would start with the points if you find that you for sure have power from the coil. they are 5 bucks at auto zone and take about five minutes to replace. they are just below the rotor inside the distributor. i replaced my coil which cost $40 because i didnt spend anytime properly diagnosing the problem and found out that all that i needed was a set of $5 points.

your post title says "HEI system." Has your electrical system been upgraded?