I'm considering adding a aux tank/tool box from Northern Tool. Looks like RDS aluminum supplies Northern tool with a gravity feed install kit. Does anyone have any experience with this?

http://www.northerntool.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=6970&productId=200315503&R=200315503

This tank has been discussed before but I'll post a link anyway.

http://www.northerntool.com/webapp/wcs/stores/servlet/ProductDisplay?storeId=6970&productId=200306721&R=200306721

RDS does supply the tanks for Northern Tool. I purchased my tank directly from RDS for about $40 more than the catalog and also got the 6 way switching device. After talking with RDS directly, their help and expertise was an extremely well spent $40 and I got to make some shipping decisions, etc., that saved me some money. There are legality problems with the gravity feed system if you get pulled over and checked in different states. I went with the 6 way switch. If you are looking at an install guide, Idle_Chatter has it pretty well described if you follow his link and pictures. I am extremely pleased with how mine turned out!