Problem of the day- 91 300E

[albions seed]

I have researched postings with similar symptoms to my current issue, but mine is different, I swear!

Today my 1991 300E started making a sound somewhere between a pronounced squeaking and grinding. The sound is coming from the front passenger side wheel well. It will make the sound during low speed right hand turns and there is no feed back to the steering wheel, i.e., vibration, clunking, etc. The car had made the same sound for a few days about a year back then it went away. This is a back up vehicle so it has only seen about 3K miles this year and only has 148K on it.

Some of the other posts have tagged this problem to ball joint, sway bar bushings, etc. I had my son try to pin point the source with the car in the driveway and the hood up. He seemed convinced that it was coming from the top of the tower and not lower down. Any clues??? I need to drive about a 120 miles a day this week and wanted to use this since my Z71 (248K) is in the shop.
Thanks in advance for any ideas. I would rather not pop a ball joint on the highway!