I am growing tired of buying Fluid Film cans for rust prevention and would like to start applying FF to the underside of my Jeep twice a year using an oilless air compressor, nozzle and hose. I hate waiting for the small compressors to constantly have to refill so what size tank should I get? I am thinking a 20-26 gallon capacity tank with 150 psi or more should do the trick. What do you think and thanks. Harbor Freight or Sears have them in the low to mid $200's.