"Also why is the shaft longer where it drives the oil pump? Do I need a different pump? With the "E" coil do you need to vent the distributor cap or taper the contact on the rotor? Sorry for all the questions."
I'm not sure of the "why" of the longer shaft, but the extra lenght simply slips over the oil pump drive shaft. As long as the distributor housing is flush with the block surface (where it is clamped down to the block), it should be fine.
I've never altered the cap in any way, so I'd have to answer "no" to the part about the cap and rotor. All of these components were engineered to work together, and they have on my applications.
As to being sorry...I always thought this type of discussion was the reason for anyone's participation in this type of forum. I'm glad to offer information, as I'm anxious as well to have someone elses knowledgeable answers to my questions. Mine are now primarily about other car types.
Hope this helps.
Good racing.
Bill