Thanks guys!
That's the one Dennis. The P.I.E. trucks that I've seen had the tag in front of the drive. I've seen pictures with the tag running singles (maybe because the belts were off?), but I think that I'm going to run duals on both axles. I may not fully detail the pulleys since they will be hid.
These are the pulleys off of my reference truck lying in the cab:
IMG_1783 by Brian Smith, on Flickr
Here is the suspension that I'm going to attempt to replicate along with the fifth wheel that will slide for a mile:
IMG_1803 by Brian Smith, on Flickr
Here is another style of suspension with the tag in back, with belts installed:
IMG_1363 by Brian Smith, on Flickr
IMG_1376 by Brian Smith, on Flickr