You obviously did a forum search and tried all the easy stuff. You can use a volt meter to check for 12v at the starter terminal ( the smaller connection )while a buddy turns the key. There is also a seperate heavy red cable which runs from the battery to the starter. Check it as well. Starter motors and solenoids do fail as would be indicated by getting 12v here but no action. Also, check the negative battery cable in the trunk which goes to the frame ( ground ). This cable sometimes gets corroded at the frame bolt. Sometimes these cables look OK on the outside, but if you peal back a little insulation, you find them completely corroded inside.

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