I'm trying to pull out the alternator on my 454Mag and there the small busing at the forward end that seems to be holding the alternator in place (the pin and tension bolt have been removed). Is there a trick to separating the alternator from the bracket? or do you just pry it?

That bushing slides in the mount, or its supposed too, frequently very tight. You will need to pry the alternator out or otherwise drive the bushing forward a little. When the alternator is out, drive it forward a little to make it easier to get the alternator back in. The through bolt will then pull it back in when tightened.

I took the pry bar to it and no go. So then I took the whole alternator and bracket assembly off the engine. Took it by the lawn and gave it a shake and it just fell off. Funny how that works! ;-)

Thats usually what I do. The three bolts on the bracket are a ton easier than that through bolt on the alt, especially if you dont have to deal with the power steering pump.