i am looking to upgrade my 1970 mustang with a Duraspark dist.  I am currently running the original 302 with points i have read several articles desribing the blue strain relief but no mention as to what year Duraspark Dist. will work.  

Is there any reason not to use your original distributor and a points to electronic ignition conversion?  The conversion is fairly simple and cheap.  

The MSD/Duraspark system is designed for hotrods.  For a driver, just upgrade to the Pertronix system.  Takes about 20 minutes to install.  You'll love it.  

The Ford duraspark ignition is a fine alternative. Its cheap, its easy and it doubles your available spark plug voltage(be sure to use the correct coil that goes with it). It will start better and run better at high rpm because it includes variable dwell timing. You can pick one at almost any junkyard. As long as you use a 302 distributor your fine , however you should match your cam and distributor gear. Later models use a steel gear and its better to go with the bronze gear in an early model. Remember to open up your point gap to about .055 with this setup. The Pertronix is a better alternative if you dont have the ability to wire in the module or you want to retain the stock distributor. The pertronix does not raise your plug voltage but only replaces the points, which in normal driving is more then adequate. The vacuum advance unit on any later model will work fine with your engine. Set your initial advance as high as you can tolerate without ping.