I spent $60 for a new optical pickup for my Raiders 3.0 that had the same issue. You do have to tear apart your distributor to replace it, but its pretty simple.

If your coil pack is getting hot without the engine running. that makes me think you have an internal failure in the coil causing it to heat up.

Richard E
1989 Montero - Stock-ish
1989 V6 Auto Raider - 5.3 Vortech Swap.
1987 Mitsubishi Starion 2.6t, soon to be 3.5
1983 Honda XL600R