Pull the coil wire out of the distributor cap and hold a half inch from a good ground. Remove cap and work points with a screwdriver, don't worry about precision just rattle them around. You should get a good blue spark or at least an orange spark with a blue streak in center. If you do then the starter draw is too great or cables insufficient. If you don't then try a jumper wire from the positive battery post straight to the + side of the coil; this eliminates all the electrical system and any possible problems in it.
