The 1/4" pickup tube should supply all the gas you need unless you plan to do extended full-throttle operation. I'd fill the tank 2/3 full with very hot water, and add 2 or 3 tablespoons of dishwashing detergent, then strap the tank down in a pickup bed and go for a drive. The sloshing action of the water and the detergent should do a good job of cleaning the crud out of the tank. Rinse several times with very hot water. A good dose of denatured alcohol will absorb any leftover water during the final rinse. Have fun!
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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