My truck started as a long box as well, and I sectioned the box 9.5". I did mine a little differently though in how I sectioned it.
I saw a 51 last weekend that used the EZ chassis swap kit, the same one that is higher over the frame. The mounts are very well made and look very easy to do, with exception of the rad support which made the truck use a very tiny rad and could have easily used a much larger radiator.
I didn't use a swap kit because of the cost, and because I would rather put the body where I want it than where someone else figured it should go. To each their own though, and that's why each one is different.
My dad's is a '52 on an S-10 frame with a 454, and mine is the 4th or 5th we've done. Feel free to send me a PM or email with any questions you have and I'll do my best to answer.
