Protecting (preserving) a 40-yr-old dashboard

[Manhattan]

The dashboards in the old Toyota trucks are notorious for cracking... a lot. This is what the dash in my '84 looked like when I bought it...

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... I was able to find a unicorn - a near perfect brown dash out of an '84 "Dolphin." Remember those tiny Toyota trucks tucked under huge campers? That overhang provided the shade to keep the dash from drying out and cracking. Yeah. Score.

I want to keep this from cracking as long as I can. The truck lives in the garage (99% of the battle). But what, if any, "treatment" should I apply? I've heard everything from baby oil (mineral oil) to 303. What would you guys do?

[Tasmania]

I would buy a dash mat we have them in Australia because the sun can do just this or even melt the dash.

Or just go with a 303 rub it in good and buff off because it needs buffing to work as per instructions.

[Desertnate]

I'd also use a windshield sun screen for those times the truck is parked outdoors.

As for products, any of the interior protectants that advertise UV protection. McKee's 37 Interior Protectant and Griots Garage Interior Detailer are a couple I use. 303 works, but overall I like products like the McKee's better.