I've got an '01 WRX and it didn't have the Brant installed (was an option way back then), and I organized insurance when I bought it I told my insurance company (RAC) and they didn't care.
Didn't affect my premiums, so ring first you might be surprised

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Its just the internet dude, its not real.
F.B. Racing
01 WRX (STI badged)
2010 XR5 Focus
06 Impreza Hatch 2.0i