I finally changed the alternator.

The brand new (ex-Delco) Remy alternator P/N 94119 ($200 from Rock Auto) fit almost perfectly, the only hitch was very minor. The plastic cap on the battery wire attaching nut not does not fit. The big weird shaped end on the battery wire fit the new item just fine even though the back of it (regulator housing) looks a little different. It is made in China but everything visible seems OEM quality. The Remy box brags that they supply these things to the car manufacturesrs themselves, so maybe it is at least American car OEM quality. Time will tell if it was a better choice than re-built.

I also changed the belt, tensioner and idler. After much thought I bought Dayco parts listed at Rock Auto. The Idler is made in Germany (bearing had the same markings as the M-B marked item I took off) and the Korean made tensioner seems well made and has a metal pulley. The belt was made in America!