I treated my leaf springs with Evaporust. I constructed a simple wood frame from 2x4's that just fit around one spring. I set it on the garage floor and lined it with 6mil poly. I placed the spring inside and added sand between the wood and poly, eventually creating a pond in the shape of the spring. I did use some containers to fill voids as I was running low on sand. It worked great and allowed me to install the second spring when I removed the first. Clean up was a breeze; simply scooped the liquid up and put it back in the jug. I had bough the 1 gallon container, which was more than enough for this purpose.