Inner fender install on 72 C20

[Nomadicflyer]

Hello, All

I spent about half an hour looking for an answer to my current challenge, couldn't find any pics or a good description here. Hopefully someone can help me out. My apologies if this has been answered recently.

I'm installing the inner fenders on the 72 C20. I've brought the inner fender up and into the outer fender, attached the bolts that face straight up into the fender. I've got one or two in along the front of the wheel arch, but nothing else wants to line up. Do I need to work the fender in differently? The tub just comes up into the fender from below, right?

FWIW, I have the large bolt with the crazy big washer on it. I see where it attaches, through the square hole and into the firewall channel. I have a new bolt kit, with j nuts and bolts. I've read about shims, but not sure where they go or how to determine what's needed. I think I have everything else I need, except a little experience.

Thanks!