I wouldn't buy the linked systems. They are just the Mopar 1970's ignition, with all its disadvantages (old electronics, needs ballast, clumsy wiring). Pertronix is easiest and uses your distributor assuming the shaft is still tight. Get Ignitor II or III since the original still needs a ballast. Another approach is to get a 1970's e-distributor, but connect it to a GM 8-pin HEI system (1985-95 V-8 trucks) which is easy to grab at any junkyard. Remove the HEI module from inside the GM distributor, coil connector, external coil and cable which connects them. It will fire off the Mopar pickup, but you need the pickup wires polarity correct (50-50 chance, one sparks better). Connect 12 V and good to go, plus get a tach signal. Biggest advantage is some engine controllers can control the spark advance (ex. Holley Commander 950). TrailBeast on the A-body forum kits as new parts for $199 if scared of junkyards. Another choice is the Ningbo "ready-to-run" distributor ($70 ebay). Use w/ an e-core coil for hottest spark. Many posts on A-body forum about all above.