If you had rotated the hub 180 degrees, then the deeper cutout would have given enough clearance to operate the adjuster through the hole in the disc (for which there should be a rubber blanking plug). Rear brakes are from a Toyota Celica, not the Supra as most people say. The difference is a 167mm drum, rather than a 170mm (I've no idea what Toyota's thinking was here!). Shoes and the retaining hardware kits can be found quite cheaply from Autodoc.

On other cars with drum brakes I have put the sprung pins in last.