Can I raise an A/C Unit and platform up maybe 5 inches without disconnecting anything?
This is such a bad idea. One of the worse sounds I have experienced is refrigerant hissing out through a pipe in a condensing unit. I tried to move a condensing unit just a inch or two so I could open up the disconnect switch to the unit to replace a contactor. The motion was enough to break the brazed connection and out came the Freon.
In addition to the refrigerant, you also have your electric supply line and a possible ground to worry about.
If you are dead set on doing this and can't wait until you replace the condensing unit as Jim Steward suggests, get an AC guy out there to remove and save your refrigerant. Then do your lifting and when done, have your refrigerant pumped back into your system.