There are two common reasons for repeated battery failures- - - -charging system problems that prevent the battery from being recharged properly, and "parasitic drain" which is a constant small current draw that drains the battery slowly when the engine isn't running. Are you using the original charging system with the alternator and regulator as separate units? if so, that was a pretty bad system when it was new, and it certainly hasn't improved during the past 60 years. I'd suggest switching to the 10-SI internally regulated alternator that came along about 1970 or so. Check for parasitic drains by disconnecting the ground cable at the battery and touching it to the battery post. If you see a spark, even a tiny one, you've got a constant current drain. Find it and fix it.
Throwing multiple parts at a problem without diagnosing it first is like a doctor writing prescriptions without examining his patient!
Jerry
