I am sending you the test procedure for the HEI, all you need is a volt meter and an ohm meter. This is out of the factory service manual and should help you find the problem. Even if the battery was dead, as long as the car will run, the battery has no say so as to how hot the spark is. All it does is supply a 12 volt source for the distributor. Let me know what you find. Thanks, XXXXX XXXXX May take more than one post. Just follow the instructions.
Sure, here you go.
Fig. 4: V8 firing order-1967-74 engines