you need a 150 watt PSU for all the toys you have. My FV24 board with P-III 933Mhz, 256MB RAM, Maxtor 160GB 5400RPM HDD alone uses 65-70 watts. I don't think your 80watt PSU will handle the additional DVD/CDRW drive, USB wireless adapter, SanDisk USB Compact flash reader, and a USB GPS antenna. You could probably get away with the bare minimum: FV24, RAM, CPU, and HDD.
Here's a question for you, what bio version are you using for overclocking? Personally I think OC a CPU for car use is a bad idea as the heat in the summer will cause the computer to freeze up.