I was thinking about this on the way home and I don't think I was clear about what I meant when I said 'index'. I am not talking about removing the locating tab from the cap, drilling a hole between the number one terminal and the coil terminal (I do this from the inside so I can make sure it is perfectly in line between the two and I also drill the hole the same diameter at the terminal on the inside of the cap) and then positively locating the cap in the perfect position...
All I meant is to bolt, clamp, screw the cap to the distributor and using a straight edge, mark the cap and distributor directly in line with the number one terminal. Ideally, the rotor will point dead center of the cap terminal in the middle of the advance range. So say you run 36 degrees total, the rotor will be dead center of the terminal at 18 degrees. Remember that the dist fires every 45 degree and with 20-30 degrees of advance, if it is off a little bit you can see that it may easily fire the wrong cylinder or two at once (particuarly on the small caps, why do you think many have such big caps!). Whenever you pull a dist and get a bad miss at say idle and it runs fine at speed (or the other way around) and/or you have to set the timing way out of whack, this is probably what you have going on.
I like to go through the whole deal with any new combination and use a little silicone plug to fill the hole in the cap. When I replace the cap, I compare the two and if it looks good, just bolt it down (lazy!)
Of course if he pulled wires, be sure they are in the right location!
ALWAYS use the procedure above when firing a new motor (and of course five minutes or so of good pre-lube and a know carb full of gas)... your cam will thank you
