Ok, this just keeps getting weirder.

While replacing the distributor, I noticed that the previous owner
had installed it "wrong" : When the crankshaft was at TDC for
cylinder #1, the distributor drive shaft was pointing at the wrong
stud (about 45 degrees clockwise of where it should be pointing as
per Bently).  Indeed, I noticed that compared to other vanagons, my
distributor seemed to be pointed much further clockwise than usual
and near the limit of its travel (i.e. the vacuum advance pointing
mostly to the right, rather than towards the front of the van).
Also, I noticed the cap was very burnt, and the rotor was burnt
exclusively on the trailing end, as if the spark were jumping to
reach the electrode).

I've replaced the Hall Generator, Coil, and Distributor.    Hooking
the timing light to the wire from the coil to the distributor, I get
indication of spark when cranking.  However, hooking the timing light
to any of the spark plug wires I get no flashing, as if the Rotor was
not lining up with the electrode in the cap.

So now I'm really confused.  I see several possible explanations:

1. I put the distributor in wrong -- I'm pretty sure this is not the
case, as I followed Bently exactly.

2. Although I have spark, it's so weak that it's not making it past
the distributor, even though everything is ok (given that i replaced
the coil, Hall sender, and distributor, I see this as very unlikely.).

3. My timing light is bad.

4. The previous owner had installed the distributor wrong ON PURPOSE,
because the engine is put together wrong???   Is it possible to
somehow get the flywheel out of sync with the camshafts, so that TDC
for the cylinder is not TDC for the camshaft?     Note that this
engine has always had a really crappy idle (i had one mechanic listen
to it and say "sounds like burnt valves?") but runs better at higher
RPMS.   I believe the history on this engine is that one head has
been replaced.

Please provide speculation as to what's wrong here.  No theory is too
outlandish.