I believe you can put springs and shocks... I would get all the stuff you need from a local junkyard out of a Ford Expedition this way you will be able to do it with no problems.
The problem with the 24" rims is they're heavy, if you put air shocks on your car it will and I assure you, you will have an unpleasant ride. But if you are going to put gas, it will compensate for the offset of the rims but make sure you will put the best gas shocks and not the cheap ones because it will wear out easily obviously because of the weight compensation and the off set
You can put Air in Air Shocks Not Air Bags
Which do i hook to to charge the freon in a 2004 ford expedition
r134a for a 2001 Ford Expedition
According to the 2006 Ford Expedition Owner Guide ( 5W-20 )
OEM air suspension? on board compressor
According to the 2007 Ford Expedition Owner Guide ( 5W-20 )
Yes.
Antifreeze has to be put in at the overflow bottle.
5 W 30 ( according to the 1999 Ford Expedition owners manual )
40-45psi on low i would use highside put it on 250