you can do plenty... but turbo setups are things ... where you primarily upgrade the turbo features... so upgrading now...u don't own anything to use...

header - has to go because it will be replaced with a turbo manifold and a down pipe from the turbo to cat

intake - will no longer be running to your TB... on a turbo car your intake runs into the turbo... then into the intercooler... and then into the TB... so it is useless to have a CAI and a header... when they will be gone anyway....

like i said.... very little can be done... start saving up and researching.... pre-turbo mods should be minimal... your tuning will suck enough as it is.... might as well make it easier on the guy doing it for you with only giving him tiny things to correct for.