The question that begs to be asked...Did Dad's "Old Skool" burn down?

I would avoid Al foil in fuse boxes (same for pennies in old house fuse boxes.)
An 8 amp circuit should draw 8 amps...you may have been drawing 30 -40 amps with Al foil...fire hazard as the smoke told you.

The fuse you describe looks like #1...My 83 300 SD fuse list shows...parking/tail light right, warning buzzer, license plate/instrument/hazard warning switch/heater and ventilation controls/rocker switches illumination/factory radio illumination.

One of those +12v leads is grounding.

The window rocker switches is a good place to start the search. Look for worn insulation/bare wire or cut wire.