Is your distributor easy to adjust for advance? Most distributors are hard to adjust as are most vacuum advance cams. That is one reason people just give up on this stuff. If you can adjust everything then I'd put as much initial in it as it will take and then work around the other issues with the springs and slots.
This is a good example of why I'm switching over to EFI. Then the whole pile of parts goes in the trash and I can set my timing curve on the computer just how I want it. No more messing around with springs and slots and vacuum ans and all of that analog crap that is so hard to set up and keep adjusted.
