I just have to say, I see Scotch-locks in some of those pictures. The first thing I would do is remove them and wire the van properly. I know, they're quick and easy, but they are also the quickest and easiest way to set your vehicle on fire. Not only do they work loose, they have exposed connection...

You can use an oxy-acetylene torch, an angle grinder with a cut-off wheel, a plasma cutter or even a jigsaw with a metal cutting blade (the last one takes the longest, however)