JOntan,
To one G9 owner to another.. this thread will give you most contributions
my 2 cents
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I tell you what I did within 3 to 6 months
1. Change leather seats to Jackspeed
2. Do VKool and Huptik for entire car
3. Change to MIchelin Tyres
4. Change to OZ Supperleggra
5. Put Tanabe Strut Brace
6. Put Rear Strut Brace
7. Change to Momo Racer steering
8. Change to TRD brake Pads
9. Did ICE (Sony HU and Helix Speakers with infitinity BOOM Box)
10. Change to TRD Air-filter
11. Change to TRD Brake Pads
12. Did Cool Air Intake
13. Did Gavninizers
14. Did Grounding
15. Lower the car using TRD Sportivo Suspension
16. Change to TOMS high pressure radiator cap
17. Change to Razo Pedals
18. Did Soundproofing
19. Change Door Handles to Premio
20. Change to Hella Horns
21. Put in Corolla-S BodyKit and change Sport Fuel Lids.
and the list goes on ...