Not to hijack your post Caddymark, but I am also in the process of deciding what to do with the radio in my 89. Cassette does not work and the rear speakers are u/s. Based on the forums I've read, there are 2 camps, maintain the original equipment or bring it up to the 21st century. I am a fence sitter and am doing both. I was about to take the center console out and do the winter project of repairing the stereo system. Surfed the net and found an alternative. this consists of replacing the 4 speakers with infinity speakers, I am not going to touch the center console, I will (have) velcroed my Dell Streak mini tablet over the cassette door and am going to get a Bluetooth radio that has a remote app that allows the Streak to control the radio (cd, phone, tuner..) I am told the I.R. needs to be line of site therefore the trunk or glove box are questionable options, I was thinking under the plastic deck cover near the battery, reachable from the front seat if required. If I sell the car in the future, I would just have to remove the radio, disco the power and reinstall the Bose speakers, no harm, no foul.
This is just an option that I am looking at and pursuing at the moment. I think it has potential. I did go the the local car stereo installer yesterday and mentioned the 89 and his eyes rolled a little. "Anything can be done with time and money.."
good luck
Mark