Interesting you bring this up.  After my 'issues' with non-starting last week, Ironsides started up just fine on Saturday, and got us around to do the weekend chores all afternoon.  I parked her for an hour and then was heading out again.  Got 100m up the road and she stopped.  She would occasionally fire again, and then just stop. 

Sheldon

Hope you found the problem, but if not, my experience with the same symptoms may help.
After at least 4 sporadic cut outs in a week (2.5 75 ), and desperate juggling of under bonnet leads, I finally found the time to investigate the problem.
It turned out to be the connecter that runs from the distributor to the ECU. The spade connecters must lose their grip over the years. After a bit of tweaking the problem has gone.

Hope this helps.

mutters