advance springs

Also, given my combo isn't stock, how will that alter how I'm gonna want to set it up?
This is going onto an 85 d150 long bed, with a 727 and 3.21 rear gear. Projected usage is mostly a daily driver, with occasional usage as the truck that it is including towing a light popup a few times a year. Elevation from sea level/ whatever Chicago is. I think we're around 500 ft above sea level.

Most of it will be as a stock super six, biggest change will be a reground #819 cam from Oregon cams. I did shave the block and head a total of 0.100"
But even with all that metal removed from the block and head, given that the head gasket I have is triple the thickness of the original steel shim head gasket, (the Aussie one) net change will be 0.060" tighter than original. Which sounds like alot, but according to calculations, when measured out, head cc'd and piston in the hole dimension figured in, I'll only be a tenth of a point or 2, of compression ratio, over advertised stock CR for the '74 slant 6, that it is. If the edges of the combustion chamber diameter shrinks a little where I can use a more conventional fel pro,etc head gasket at 0.040" (still 2x the thickness of the steel shim gasket that was original) I'm gonna be about 8.8-8.9:1.
So given that, what amount of initial, mechanical, and vacuum advance and at what rpms should I be shooting for?