I have never seen paper/gasket on the inside of the bands of a starter or generator; however, my experience is limited to only about 30 different GMC and Chevrolet used starters & generators.
I have also had 48-55 starters and generators rebuilt by professional re-builders over many years (starter and generator specialists) and they never put paper/gasket under those bands.
This does not mean that the paper was not there originally but the paper/gasket did not seem to be needed (the bands produced a very tight closure without paper/gasket).
Tim
