bolt circle diameter for JBL 2435 HPL

[low pitch]

Hi, First post. I am making horns for a customer and I need to know the bolt circle for JBL 2435 HPL compression drivers. Seems like it is not the usual 4.5". I scaled a a photo I found here on the website and looks more like 3.25" diameter bolt circle. Thanks for any help.

martin (azurahorn)

[yggdrasil]

d= 8.25cm

[low pitch]

thanks