Fresh Air Vents

I have a 1989 S10 pickup,2.5 liter engine, with vacuum problems. The A/C and heat controls do not work, I only get air thru defroster or floor, this truck has been setting up for 2.5 or three years, some of the small plastic vacuum lines under the dash have deteriated and I have spliced them with I/V Tubing and would like to replace them with the right kind of tubing but am having trouble locating it. I also need the air vent actuator located under cowling on passenger side of vehicle, how many of these actuators are on the truck and where are they located? Any info on locating these parts and info or advice on troubleshooting these problems would be greatly appreciated, Thanks in advance, CS10

Rubber vacuum hose workes good.
Check for good vacuum from engine and vacuum ball to heater controls.

Thanks for the reply, and I will go look again, a little closer I guess, thanks again.

Find and check the cabin air filter.
Good Luck
MT