Personal horn button size?

[Mr. Burns]

I have a beautiful Personal Wheel I'd like to mount into my E30.
I have a bunch of Momo horn buttons, and a Nardi. the Nardi just seems to fit...I'm wondering if Personal has it's own unique size?

I'll likely go hunting online and pick one up on the cheap (knockoff or legit) just to get this going...

my measurement is 55mm...makes sense?

[glnr13]

at work right now but I will measure my horn when i get home in 4-5 hours.

[glnr13]

[Mr. Burns]

super! Thank you sir:)