i don't think anyone will admit to insuring there car without declaring there mods
i definitly wouldn't
i'm insured with warwick davis with all mods declared and pay £495 fully comp,a quote from norwich union in standard form wasn't much cheaper
be safe rather than sorry , if you get hit and the assessor checks your car then he has the right to basically tell you to f..k off
35,garaged,cat 1 , full ncb , massive list of mods .