Well, don't just take my word for it, if you think it looks good. I happen to think the US spoiler like James' one looks good on a black or dark car. It is low and elegant, and those in the know will understand yours is UK once they see the glass headlights and the headlights washers. JDM cars never got those, nor US cars either.
If you like the look of it, go for it!!
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Black Betty [Bam a Lam!] '93 UK spec, still languishing
Betty
Jersey Girl Silver '92 UK [Channel Isles] 40K
Jersey Girl @ Mersea
Candy Purple Honda Blackbird
Plum Dangerous
White X2 RVR Mitsubishi 1800GDI.
Vantastic
40,000 miles Jersey Girl