Bride side mount measurements

[The ROMAN]

I just got this Ultrashield circuit seat. It's custom made for me and all aluminum with padding over the shell. My question is can I use Bride side mounts like FG or FX type to mount it? The seat is 17 1/2 inchs wide at the base, which is wider then the stock seat mounts. Are the Bride mounts too narrow? I can't find a measurement on them. Or if anyone has modified bride side mounts for a wider seat?

Thanks