Brainstorming Ideas for 400-450 hp 360 Build

Hello,

Here's what I'm trying to achieve before we get to the engine. Vehicle is a 70 Duster, 4 speed and I want to keeping it a manual. Looking to have a fun car that I will drive around the street during the 6 or so months that the weather permits (but it won't be my daily driver). Will also do some drag racing a couple times a year and possibly some auto cross. So it will get hammered on.

I have a 360 motor out of a 1980 truck I got for next to nothing as the duster currently has a 318 and I want to stay with a small block. What should I be putting my money towards and how much should I budget? I'm looking for the motor to last and I would like to run pump gas (91 octane premium is fine). Let the games begin....