All the A/C parts for the 91 Explorer, like hoses, blower motor, etc call out two different part numbers. One is marked "To 4/91" and another "From 4/91". Was there some kind of significant change at April 1991?
I'm kind of puzzled what to do because my A/C compressor, dryer, etc are replacements installed in 2001, so which parts do I use? I have a leaking compressor hose that needs to be replaced but don't know which part to buy.