I'm partway through replacing the brake shoes on a Model B I'm recommissioning. The old shoes had completely disintegrated and were a pig to remove. I've got some reproduction shoes from a supplier here in the UK and tried to fit them yesterday but ran into an issue. After fitting the shoes, pins, brake arm, spring etc I tried refitting the wheel arches. Even with the adjusters backed off as much as possible (with only a couple of threads left in the nuts) the brake arms still won't retract enough to permit the arches to be fitted. The wheels lock (i.e. the brakes are completely engaged) before the arms can be rotated up and back enough to allow clearance for the arches when fitted. I've fitted everything as per the manual and I can't see a way of getting the brake arms any further back/up. My only thought is that the friction material on the replacement brake shoes is thicker than on the OEM shoes reducing the available free play at the brake arm. 

Any advice would be greatly appreciated on how to rectify the issue. My only present thought, assuming I've not done something daft and easily rectifiable, would be to make up some adjustment screws which are half an inch or so longer than the originals to allow the brake arm to clear the arches. 

I ran into the same issue with my left side brakes, just recently. It's a long story as to why I had brake shoes from two different distributors. Being that you are in the UK, is it safe to assume that you have an IB?

Anyway, I returned the culprit brake shoe/pad and ordered another from the distributor that offered the shoe/pad that worked perfectly on my right side. Installed perfectly.

edit to add:

I do not believe a longer adjusting bolt is going to resolve your issue, if I am understanding your problem correctly. The length of the bolt isn't the issue, or at least it wasn't for me when I had this problem with my left side installation. I used the same adjuster bolt with the brake shoe/pad that did work.

That was the advice I was given by the distributor I bought the culprit brake band from Paul, but by that time I had ordered and received the band from the other distributor. I suspect that would have worked, but I didn't know it until I had installed the second band I had purchased.

I suspect that the difference could not have been more than 1/8 of an inch. It was that close.

I was a bit impatient when ordering, I could have avoided this situation if I had not ordered on the fly, i.e., at the time we were pulling the right side brake band.

Anyway, it all worked out for me in the end.

edit to add:

I am not going to mention the distributors, because I'm pretty sure that the issue I experienced was due to impatience on my end, and not the quality of the products ordered from either distributor.