I have an MSD ignition box in the trunk of my ‘95 GT and today I made a cover for it out of things that I had around the house.
I used an old Swiffer wet mop pad refill container (they also make decent storage boxes if you keep the lid). I cut the slots for the wires and then I sprayed the inside fairly liberally with spray foam insulation so now it’s pretty rigid and fits the box well. Next, I scuffed it up a little with some sandpaper and then I painted it with a few coats of black...

Homemade Ignition Box Cover