It may not hurt you guys to take a look at Leo Santucci's book, "Chevrolet Inline Six-Cylinder".
He has a lot of info about the different gears including the steel cam gear, which is usually used in hi-po engine builds. He also tells you about the thrust washer, the spacer ring and how to install the gear.
I tried following his exact directions and had trouble. I may have been too slow or didn't have the gear hot enough. As a backup I had set my press up ahead of time. When I set the gear on the cam, it stopped about half way on. I immediately pressed it the rest of the way. I found a little sliver of aluminum around the nub of the cam. I checked the runout and found it to be about four times the allowed .004". Scratch one new cam gear.
On the next try, I put the frozen cam in the vice. Set the hot gear on the cam and it dropped half way as before. This time I had the torch with the Rosebud tip sitting there. I waved the Rosebud around the gear about three times and it dropped with a "clink" sound.
Run out was perfect.

'67 GMC 3/4 292 4spd