As far as OEM Processor Upgrades, it all depends on what Features you want. From my Experience Both the Alpine Modules & the 360.1 & .2 are worthless if you are Going "Active."
3-Ways can be a B*tch to set up. Have you checked your PLD's? -I have a feeling if you leave them "as is," you're going to have a tough time battling Reflection. Get them in the Pillars
Also, I am only assuming you will be using Polyester. You may want to Drill some Holes to help the Resin Adhere. Polyester has a tough time adhering to Plastics, but maybe you have some Epoxy on hand