That's a pretty cool article. I remember when the vortec heads first became popular a 350 with the Hot cam dual plane high rise, good carb and headers would make an easy 410 HP, just like test 4 in the article you linked.

I agree you're building a monster there. I tuned a 406 SB with Etec 170 heads, a Stealthram and a very mild 219/227 at 0.050" hydraulic roller. Based on lb/hr fuel used and 0.50 bsfc it was making 450 HP. I think your changes will bump the power peak 400-500 rpm and add 40-50 flywheel hp over your current combo. Install 1.6 intake rockers if you can. It will make a difference.