Hi Bruce,
Thank you for your considered and thorough response to answer my questions.
Yes, I am using the Assembly drawings also. My basic 1971 1/2 ton wheels/rims are the 5-lug configuration and the mounting bracket I located had to be modified from 6 to 5 lug with 1/2"-20 bolts. The fender with the cutout for the SWB was located in a wrecking yard up in Orange, CA and needed a bit of touch up body work to restore. Along with it came the original upper and lower rear supports which I am using. I had the front support assy fabricated by the weld shop at the shipyard where I worked, and I found the bottom support through the GM parts system.
You're right - the hole in the bedside for the fender is the pilot for all other mounting fasteners to match. My fitup problem, now solved, was with attaching the bottom bracket to the front and rear vertical supports. The bottom holes in the verticals have now been plug-welded and ground smooth for redrilling to suit the 3/8" square holes in the horizontal bottom support under the wood.
Here is a pic of the loose fitup on the bench.
Thanks for the pic of the clearance between your tire and bed rail. I have sufficient length of the mounting bolts in order to make up the clearance.
The grommet through the fender: I didn't realize that you had custom made your own. I may end up using the new original size grommet I located which is suitable but flimsy.
I am holding in abeyance the undercoating of the bed side under the fender in consideration of your response.
As far as seam sealing on the bed assembly, and as you responded, I was talking about the tailgate, but also the edges of the stake pocket assemblies which are stitch or spot welded to the bedsides appear to need it. The tire cutout edges on the fender were sealed when the restoration was done.
Finally, Bruce, I will follow your example and install the inner fenders after the outer fenders are installed and lined up. These assemblies are all original with the truck and should not pose much of a fitup problem.
I don't know if the photo I wanted to attach made it or not! I hope it was attached.
Thanks ever so much for your help. If I'm ever up there, or you down here, I'd like to meet you and see your outstanding project.
Chuck