Thanks Purtsi, I'm trying to find a conversion that'll keep the track as close to standard as possible. That's why I'm interested in whether that's what looks like a spacer at the wheel mounting side of the disc and whether it's got to be a specific size.
The car's very original so I'd rather try to keep away from alloys and arches if possible.
Unless I get lucky I guess this may mean splashing out Cooper S stylee...
I think the problem is the caliper fouls on the standard steel rim as they are a 2 piece design and it catches on the wheel center which is welded onto the outer rim causing a lip. I'm not shaw if this will help as the problem is due to the caliper spacing from the center of the hub so you can fit the 7.9" disc, and looking at the posts I don't think this changes. But Purtsi is you man... I would think it should be easy to get the spacers made up if you can get the sizes???
It should track differently as you wont need to use the disc brake CV's, flanges, etc so it wont be 1" wider. (P.S I dont think you can use the timkin bearings with the drum brake setup, but I don't know if they were introduced to cope with as the track of the car or another reason???)