[elhigh]

Rear wheel skirts would be a great addition. If you have any kind of bodywork skill at all, it shouldn't be too hard to prime and color the skirts once you've got them made. Do a nice job and they'll look almost factory - and when you hit that state, you know who sees the mods? Guys. If it looks factory, 99.44% of all women will never ever notice it.

Under your van is a topographical nightmare. A bellypan is totally invisible, but will yield real results.