For a slightly different view, I did a thirty-over 390 several years ago. I started with a '64 PI engine and added a Comp solid roller, and a set of Dove F-5 heads and a Dove 'spider' manifold. The heads and intake were massaged and matched by Wayne Kuchtyn at 'Headwinds' in Westland, MI. We used Ross flat-top pistons which created about 11.5-1 compression and used 2.100 nailhead intake valves and 1.65 tulip exhausts from Ferrea. We chose the cam specs to approximate the street characteristics you might get from the use of the factory 'AA' cam.
It's more story than is necessary here, but the break-in pulls on a dyno at Roush's Livonia facility produced +/- 500 HP with a fat fuel curve and with only 32 degrees of ignition, so there was likely somewhat more to be had.
Barry's head design is, for all practical purposes, as up-to-date as exists and if you were to use them, or alternatively a pair of Dove's F-5 offerings, your goal is surely within reach.
Good Luck!
KS