My son and I have completely stripped our '74 Scamp in preparation for painting and some repairs. What should I upgrade or do while I have the dash out? Should I change out the heater core or make any repairs to the HVAC unit? I need to replace the vent hoses as they are deteriorating. I am wondering about any of the 30 year old seals in the ducting system. I have no history about how it was working prior to me getting the car.

Also should I do any repairs or replacement of any of the dash gauges or support electronics? Wiring or electronics components? Also if he we want to put in a decent radio is there any wiring upgrades I should consider while I am at this level of disassembly?

Thanks.