@911monty:
Good idea, but if he would have a low fuel pressure i think all cylinders/sparks would be affected the same way. Please take a look at the picture of the sparks (i know you did):
Misfire, no codes
But maybe it's a good idea to check the fuel pressure too, because fuel pumps on these cars tends to get fatigue and the sparks look more black and white than brown.
Just my 2 cents.
Regards, Markus