LT-4 With Hot Cam using LT1 edit. How much can you advance the timing?

Hi, I have a lt-4 383 stoker with LT-4 Hot Cam. I had the OBD II computer tuned by a local tuner. He left the timing stock LT4 except for the 4000 to 6000 rpm range. He advanced the 4000 to 6000 range 2 degrees. He ran auto tap after that and did not pick up any knocks. Does any one have a similar set up and did you program it with lt1 edit? How far did you advance your timing and how much at what RPM ranges?
Thanks, Michael