Did you ever notice that when you time a stock ignition system that when you shine the timing light on the timing marks that the marks always seem to move around a little bit? Locking out a distributer eliminates ALL of the movement on those timing marks completely irregardless of engine speed, RPM fluctuation at idle, etc...

Before you do anything, you're going to want to set your engine's initial timing at 36 degree's (don't rev up your engine after you set the engine's intiial timing at 36), shut the engine off, and then make sure your engine will still start with 36 degree's initial advance. If it still starts up,  to lock out any distributer all you need to do is remove the mechanical advance springs and tach weld the mechanical weights to the platform the weights are mounted to. Set timing anywhere from 35 to 38 and let her rip. No more I think it's at 12 before TDC, etc... This is a extremely common modification to drag cars and allmost all blower engines. 

You will still get some inconsistancy due to slop in the cam chain and dist/cam gear unless you go to a crank trigger ignition setup. Less slop with newer parts, more with older. With a crank trigger, the timing marks look painted on, you wouldn't believe it! Being of the anal-type, when I installed my first trigger, I installed a DPDT switch so I could switch back and forth between the dist. and crank trigger to see what difference there was. I have not used a conventional setup on any serious deal since.   TIMINATOR

If you want to see the cam twist, hold it at 2500 rpm, then whack the throttle hard, the momentary retard is the cam twist, and timing chain stretch. NASCAR motor builders calculate the twist at the intended operating rpm, and compensate by advancing every lobe from front to back!   TIMINATOR      anal is short for analyze! at least in my world!