i want to put the leaf springs on TOP of my axles.... what do i need to do?

First save up a lot of money. Next seriously consider the down side: very expensive, a much less comfortable ride, a higher probability of tiping over, much reduced value of the automobile and, its already been done. Conside the last part, its already been done, find a raised rig and buy it for less than doin it yourself. There are a lot of modified Cruisers out there for sale on CraigsList, Cars.Com and elsewhere. The Cruiser you have can be restored and sold for more than what you put into it. If your'e determined however, www.manafre.com has good parts and advice. There are many other cruiser sites as well. Coolcruisers.com comes to mind there are many more. Get your used parts from www.cruiserparts.net.