Need electrical help- no spark., HHHHHHHELP! Options

[tornik550]

I built a /6 2.7 this past winter. I originally ran the engine on a test stand so I could work out all of the bugs. The engine ran great. I had a fairly simple electrical setup and I did not hook up my alternator. Since everything was workin well, I installed the engine in my 914. Once hooked up, I started the car and it ran great for a few minutes than I had to turn it off for unrelated reasons. A week later, I tried to start it up again and everything worked great. Then a couple of days ago, I tried to start the car and after the engine would crank awhile, you could occasionally hear a cylinder fire but the engine never started. Since then, I have not been able to get the engine to start or even any signs of spark.

To check for spark, I hooked up a plug wire to an old spark plug, layer it on the engine, cranked it and looked for spark.

I have a msd blaster 2 coil, pertronix ignition, new distributor cap and rotor, new clewett wires.

Here is what I have tried- none has worked- I tried the above test with each of the listed changes.
-I have tried three different pertronix ignitors (two brand new)
-tried three difference could- Bosch blue, msd blaster 2, accel super stock (none of the three are new- I thought they work ok however?)
-I tried a new set of points (I did get one spark 1 time)
-I have an msd 6al- no luck
-battery has 12.8v

I even tried rewiring everything as though it was on the test stand. Nothing was hooked up to the car- everything was directly to a separate battery
-12v to starter
-switched 12v to starter
-pertronix + wire to + post on coil, - wire to - post
-switched 12v to +post on coil
-ground to -coil post

That is all that was hooked up and still no spark!!! Spark plugs are brand new also. I just don't get it- I have mega simplified the system- everything worked fine and now nothing. I don't even car if the engine doesn't fire- as long as I am getting a spark, I can work from there.