I had a similar problem this week.
Last Sunday I removed my stock radio and installed a used third party radio. Works great. Went for a 100 mile ride. No problems.
Tuesday evening took it to a local dinner-meeting. No problems.
Thursday evening I planned to take it to a local cruise-in.
Got in. No lights. No horn. No radio. Battery was completely dead.
It is a 7 year old Delco, top post.
I did dis-connect the pos when I was replacing the radio and put it back on tight.
I dropped off the battery to my local shop on Friday and will call them on Monday to get the news on whether it is toast or not.
Hate to spend $100 on a new battery now.
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