I just looked over the whole build looks good. I'm digging the rolled tube on the back half it looks really good i wanted to do that but i'm not sure of anyone around here that has a roller.
As far as the inboarded sprigns go my friend ran them but he went to far in towards the third and it had some problems striping out the nuts on the u bolts, other then that they work awesome from what I have seen.
Do you know how long the explorer springs are?