Ive been doing a little research trying to figure out what Im going to do to the P5. I think I have a good idea as to what things Im going to do on the car:

Mazda 626 Single Runner Intake Manifold - Extrude Hone or Port and Polish (Still deciding) http://www.extrudehone.com/pwrfloprice.html $$$$$

Lower Compression Pistons (Custom Crower Forged Rods, Dished Piston Heads etc) For higher boost, Im going for around 14psi.

Mazdaspeed Exhaust Cam, I know cams dont do much for Forced Induction, I do believe that leaving no trace of exhaust fumes in the combustion chamber would lead to better fuel maps.

Spool Shorty Turbo Manifold or Spool Full Tubular Manifold (again havent decided yet, comes down to how much cash I have at the time. http://www.spool-turbo.com/tk03.html ) Extrude Hone for better air flow.
*Note: I havent found a part number on the MSP Turbo Manifold yet. I also havent looked into the FM Turbo Manifold.

T28 or 16G Turbo, 16G = Better horsepower, FWD car more HP isnt that great . T28 Turbo seems to be ideal for our engines (spooling up around 2.5k rpms).

Custom Piping for FMIC. I will go with a Spearco Intercooler, In my opinion these are #1 for your money.

PWR Performace Radiator. With a turbo setup its hard to keep the engine running at good temp. I havent looked for an oil radiator yet, im sure that would be a good investment too.

Upgraded Clutch and Flywheel (I havent researched much here).
Ive heard Tilton is developing an amazing 3 puck clutch that is VERY worth while for the street, this is a custom job and takes a lot of cash. As far as other Transmission equip Im not sure what else you would need to make the Tranny beefier.

Quaife LSD or the Mazdaspeed LSD both have excellent feedback and with the HP that I am hoping to produce this seems like a must. (Just a matter of how much money I have at the time).

Edit: I cant believe I forgot this stuff: Haltech Programable ECU, 3rd Gen Supra Fuel Pump, and of course better spark plugs. I am also talking to a guy about a custom stainless steel exhaust.(Thanks Charger )

I will add more as I go along these are just some thoughts I have written down over a week or so.

 

sounds pretty darn good to me! Good planning is the start of a great car. Hope you have some fuel and ignition upgrades on the continuation of your list.