This is fantastic! the work on the door and boot hinges, and the inside of the boot is absolutely amazing.
The boot board is perfect, the fuel tank looks to be a later model 9gal (common upgrade), but the only thing missing is the details on the inside of the boot lid... there is this type
and the double skinned (this is what I would go with on the mk1)
I've been lurking these forums for a couple weeks - just getting into scale models again. I had done a 1:24 (fujimi) scale replica of my 1:1 Mini (I have 3 1:1 minis - one driver, one project, and well... the remains of another).
I'm building a Mini speedster right now (similar to the minispeed/vmax car) and a stock cooper s from this same kit you're building (edit- oops, no mine are the tamiya kit).
I am absolutely blown away by your model, thanks so much for sharing