These are awesome little vans. I was very tempted on getting a 4wd one and making it into a camper like you're doing. I found a few on them on CL in the bay area about three months back. One that had a ladder rack in the rear and a front bumper with a winch that has been through Hollister many times supposedly. They are also going for a lot cheaper than VW vanagons and are a lot more reliable too. There was a few on there with over 300k miles on the original engine. Though like most of these 30 plus old toyota's they need some love. Can't wait to see your progress on this!
