1980 is a stamped steel version. Direct replacement for the earlier cast steel version. My experience has shown that the earlier bracket is a better way to go as it holds the compressor more solidly than the 1980 version which allows for more flex/movement.
If I had any pic's I would post them up, but I don't. The '80 brackets are different from the older 1's. Post up some pics of wha you have, then maybe we can figure it out ?
I bought a motor and tranny last year for my project and got just boxes and boxes of parts..... Went into my shed and dug through some boxes and came across this.
The reason I asked in the first place was that I had a bunch of bare brackets and didn't know what went to alt, comp or ps. A quick dig as you can see answered that question for me