Hi, I'm working on a 42 1/2 ton Chevy pickup and it is a stepside short bed and was wondering, there are three bed sill crossmebers for that bed and I know where two go, the one in the front and the one behind the rearend that bolt to the frame, but not sure where the three one goes, and does it bolt to the frame too,also do you need to put angle iron on the side of the bed for a wood striped bed, thanks for any input and if anybody have any pictures they can post that would be great