Definitely electrical related.

Could be a wire in the engine compartment got hot, insulation melted
and shorted out against ground...or a ground wire broke in the engine
compartment.

Try the swapping ECU first.  You don't need to mount the ECU to try
another one, just unhook the big plug while the old one is still in
the van.  (The ECU does not depend on the chassis for it's ground).

If another ECU doesn't run your van use a voltmeter and start doing
the ECU measurements from the bentley.

>An immediate shut off of the engine couid very well be the pickup in the
>distributor has failed.
>
>Pretty common.