[Tx Firefighter]

You can also narrow down the vintage of the pan by the heater control. Early cars had a turny knob that stuck out of the tunnel while later cars had two lift levers, one on each side of the park brake handle.

With the IRS though, I'd wager the pan is 68+ vintage. It's kind of a trip to take to convert swing axle to IRS so you don't see if often.

Sorry for geeking out on the details here. I was a hardcore air cooled guy for a long time and have cussed and sweated over a bunch of them.