My set up is very similar. 331 turbo but its a 88 notch.
If your going to do it get Mega Squirt or Stinger stand alone PCM. There's a huge help thread here for MS based products.
I went with on3 for the turbo kit. Minor issues and some fabrication. The on3 turbo is getting upgraded....eventually.
Also, I went with MSPNP2 because it was plug and play. Way cheaper to build your own. Wish I would've went with MS3 ( controls a lot more stuff ).