TonyTiger - Have not heard from you in ages. I don't know what you have tried to track down the drain on your previous batteries. That is like trying to find a needle in a haystack. I would remove a battery post and alligator clip a volt meter in series with the post and removed cable. It should show if there is current flow. If there is, then the draw is prior to the ignition switch. I would next look for how the radio/clock is wired and disconnect if at all possible. The clock is expected to have a small milli-amp draw, but should not kill a fully charged 12V battery in several months. I would then use my volt meter to test if circuits are live in the fuse panel without the ignition switch on (most are not). If there are one or two, I would remove the fuses one at a time to pinpoint the problem cirucit. A real guessing game, good luck.