We pulled the old dizzy and installed a MSD Pro Billet Distributor. We set the centrifugal advance springs (light blue springs) to smaller ones (one light blue and one small silver spring), advance comes in earlier, while the initial advance a little more retarded. The base timing is set at 12.
 

 

 

 

 
 
 

 

 

 

 
With the new large diameter wires, the brackets to hold the wires needed to have the holes drilled  larger.
 
 
 
Although the firewall had been malletized, clearance was still too close.  What we did was to rotate the dizzy two gear teeth, then repositioned the spark plug wires to compensate.  This method worked.
 

 

 
I wanted a cleaner look, and better access to the plug wires, so we set about cutting off the unnecessary bracket that supports the water pipe.  A few quick passes with a hand file took off any sharp edges.
The spark plug caps of the forward wires often contact the firewall, especially when the large cap design is used.  Even with the small cap they were close. 
 
 

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