if your AC lines are all disconnected then the freon is probably already gone. it should be fine. i dont know what all you have off of yours but obviously dont have anything hanging loose and dont try to turn on the A/C.

 

unplug the a/c compressor connector, should have just 2 wires in a small connector. the a/c turns on during a number of functions, including defrost, and if it does with no freon it will burn itself out very quickly because no oil is passing thru it.

 

Actually if the compressor doesn't have enough freon in the lines the clutch will automatically not engage.

 

yeah, the truck's been on blocks for 2 years and i've got almost everything back together, i'm waiting on the air box, but i'm itching to drive it, so it should still have all the freon in it, none of the hoses have been disconnected, just the fan box and the side of the big plastic thing. I was going to just screw a piece of sheet metal over the hole where the fan goes into the firewall, so if i did that and unplugged the compressor everything should be ok? I should also mention that at one point i was going with a vintage air setup so i cut the wires from the controls to send to the vintage air people so i could use my stock controls. so you don't have to worry about it kicking on, lol

 

as long as its only the plastic box that is gone, there is nothing to worry about. it wont hurt anything having the holes in the f.w. you fan stuff wont affect the driveability of the truck.