Well, here's mine:
Excuse the lack of carpet and general messyness there - I was doing a number of things at once.
I actually measured it all up and cut it out myself, and then found this on the net: instuctions and plans for the exact same thing I just did. There should be a link from this page to the plans:
http://www.theminiforum.co.uk/forums/in ... wtopic=445
Another interesting topic: The Mini Dashboard Directory
http://www.theminiforum.co.uk/forums/in ... opic=69001
There are some pretty amazing dashboards on here!
As for tips:
I laminated the wood to a thin piece of plywood to stop it from warping. Which was a bit silly, because that means that the blackwood shrank and the plywood stayed the same, so the dash actually curves both horizontally and vertically. It's a pain to mount flat speakers and a glove box onto a curved surface.
I used exterior varnish to finish it (because they have UV absorbers). It actually came up pretty well, and a lot cheaper than spraying it.
Hope it goes well.