32 degrees total is very little. I do perfromance tuning, and usually end up in the 36-38 degree range for total, all in by 3000 rpm, and 18-20 initial. More timing increases vacuum which makes it run much better. Use a vacuum advance as well, with 10-15 degrees of advance built in. You should be able to cruise under no load at 48-55 degrees of total advance.
A performance engine can run with a SM420 trans, but tuning is critical. The torque band needs to be widened as much as possible. You have the cubes to build the torque, so make the best of what you have.
Devin
