This is a chart of most cam grinds for the FE during the sixties. The C6OZ 6250-B should be sufficient for above normal street duty (stock on 390GT and 428CJ) and has a very stable idle.
The choice for myself would be the C8AZ 6250-C. Put one in a '67 FAIRLANE GT 390 and really woke the thing up. Just a little noticeable rumble.
There are also 427 mechanical grinds listed for those not so faint of heart. The nice thing about a roller is you can stuff a lot more events into the cam without the objectionable rumble.
Anyways, I hope we can get enough people together to at least order the cores.