Going for the Spectra tank was a smart move. I did that after trying to clean my original tank. It sat with old gas in it for 25 years. When I drained it it left a horrible sticky residue. It seems like a crazy idea now but I followed others suggestion of strapping the tank to a jacked up tractor wheel and running it with gravel inside the tank. After about 20 minutes of that all I ended up with was a tank full of sticky residue with gravel stuck to it.
