I built my suspension in pieces, and I took pictures of my truck throughout. I made the chart below to help show what drop you'll get with various combinations of Porterbuilt parts. Let me know if you have any questions.
Here's a link to the chart in full size:
https://dl.dropboxusercontent.com/u/...%27s%20C10.pdf
Here's a link to the thread I did about my suspension. Some questions are answered here too:
http://67-72chevytrucks.com/vboard/s...d.php?t=609897
GOOD LUCK!