I've been to Padworth Breakers. That little MK1 wasn't quite as bad as that when I looked, but was far far far gone even then... 
I first saw it when I was doing my work experience at a local garage and we went up their to drop a car off. That was about 4 years ago and it was well past it then. Never mind I know one person on here asked for the address of the place and popped over their and got a few bits off the mk1 just before the scraped it so at least its helping put another mini back on the road.
It's gone now
I got some bits off it a while back.
Went up there about a month back to strip everything I could from it, and it was gone. There was so much more on it that I wanted; air vents, voltage control box, headlights......
Bummer. Anyone know of any other MK1's sitting in a scrappy?
Good luck with the front end build. I used cheap panels on my last mini. Putting the panels together was a bit of a struggle, I could never get them to line up perfect. A bit of filler in a few places helped. Like you say it will be a good learning curve for you. Because of my lesson, I'm using genuine panels on the front of my mk1.
Just take your time, and if at first it doesn't go together right, take a step back and try again.