Thks Richard I plan to identify fatmat

I used Fatmat all over, including the roof, then the Dynamat Hoodliner (different type of foam) on the hood.

Make sure what you use is Butyl, not asphalt. Asphalt will smell and may fall off if it gets hot. May drip into the headliner if on the roof. You really don't need more than one layer. 50 sq feet will do you.

I used a generic Dynamat, it is a bitumen with silver foil. While I didn't cover the entire car, I did put some on all the inside panels, and the roof, and the car sounds very solid, not tinny or echo-y

I built a MK2 Mini several years ago and used 125 square feet of Dynamat.  I had two layers on the roof, doors, and sides, and I put three layers on the floor, under the dash, and behind the bulkhead.  Absolute overkill but it is the only Mini I have ever ridden in that didn't have any squeeks or rattles whatsoever.  Plus it felt like a tank when you shut the doors or knocked on the roof, etc.  

Sean which insulation did you use for your doors and did you consider inside the roof?

I just fit some dynamat style insulation in a set of MK1 doors, and the cards fit just fine.

Plus the doors now close with the quiet 'thump" of a Jaguar...

Considering putting some insulation in the doors. Is there any interference problems when refitting the door cards?