Also, raise the front end, remove the belly pan, and look at the grounding wire for the alternator, especially at the point of attachment to ground (should go to a bolt attaching the lower alternator bracket to the engine). Inspect it carefully and replace the ground wire if any signs of damage. This location took the brunt of the current when I did a similar thing on a 87 240, damaging the ground wire there; except I crossed the terminals with a new oil filter. There were burn marks on the filter, but I didn't notice a problem with the car until a year later, when I started having severe charging problems and thought I had a bad alternator. That wire had burned at the lower ground connection, but wasn't bad enough to cause problems right away. Wear and tear at that spot over a year was though. I found the problem accidentally after I caused one of the alternator bushings to pop out when reinstallingt the alternator, after it had been removed for testing at a shop. When I went under the car to get a better look from below to align the alternator in the bracket, I happened to see melted insulation at the connection. I then yanked the wire off and saw that only a few of the internal copper wires were intact. The remaining wires were severed and oxidized. I replaced the ground with new wire and fixed the problem. I had caused the short right after a rebuilt alternator and wiring harness had been installed. Fortunately, no apparent damage to the alternator. I now cover the alternator posts with electrical wire (they didn't come with rubber caps) and, like the others, disconnect the battery before changing oil filters. It was a $1.00 fix, if don't count the time involved and the tip I gave to the AAA tow truck driver.