I'm got the front of my van gutted right now, doing all of the things you and others have mentioned. If you can, I'd add treating rust to the list. Might be none, but might have some seams that could use attention.

While you've got the heater box apart, replace the foam on the flaps. And the gasket foam that seals the box to the body. And maybe replace the resistor that lives in the box.

Check your brake booster. Bentley explains how to diagnose.

Also check the tubing for the washer fluid jets. Way easier to replace it with the dash out if the tubing is kinked or getting brittle.

Are your power window switches okay? If you're thinking of relocating them to the dash, now's the time.

-Jarrett Kupcinski