previous post, the problem with the guard irons wasn't that they were too long, but that I hadn't bent them to shape. Embarrassingly that was the next step in the instructions. As you can see though the chassis has moved on a little further than the guard irons.
The main chassis etch contained the outline of the springs but no detail other than a few rivets. Al the details are provided by overlays. The first job was to ream out the holes in the axleboxes so that they fit around the protruding bearings before they were soldered to the side of the chassis. Once they were fitted the spring detail etches were filed to to fit and then soldered in place.
The next step solder the rest of the chassis retaining parts in place, which means that the wheels will be permanently trapped between the outside frames. I'm currently debating if it is worth trying to add the remaining details to the chassis first so I can paint it without risking bunging up the wheels and moving parts, but the consensus seems to be to finish the model first (at least to the point of wheels, pickups, and fly cranks) and then paint it. If anyone has any thoughts though I'd appreciate any suggestions.