Saje Brian morrow was in Kempsey sporting car club so you may be able to contact him through them, where abouts in the blue. Mountains are you as I'm working at Lithgow and would like to have a look
Metric? All my Lockheed brake fittings on the Renaults are imperial and the brake places can make up a new hose with new material to Australian standards. They have had the correct end fittings in stock every time I've needed hoses. $50 per hose last time I think, not bad when you consider Audi service places charge, I'm told, over $200 per hour.... I've given up buying hoses of indeterminate age from OS.
Maybe R12s are metric, but R8/10 are certainly not.
I don't know what the guy was on about and I didn't check because I didn't need to have new hoses made. But that's what he said. Maybe he was trying to pull my leg. For 400$ it was worth a shot.
Now considering your brakes are Lockheed, (perhaps Aussie content?) maybe that explains why they are imperial. Not sure what the brakes on my R12 were.
Overseas, I would be surprised if anything was not metric. After all the french invented the metric system.
As others have hinted at, there aren't many period engines that would not require work to get near 100hp.
Having said that, there is a bit of work going on with fitting latter twin cam Clio engines (k4m k4j etc etc) to those standard 12/10/8 gearboxes.
I think we decided a custome flywheel to assist in lining up a starter motor (although you could push start that thing) and did we have to change the input shaft? The bell housing is unchanged and lines up (which means you are half way there)
All engine mounting points would change, but it sounds like you could muster that.