I am in the process of building an electric guitar
and I am inspired by the model mentioned in the
title. I don't know the exact thickness of its body,
though. Could any owner of this guitar measure
this distance and post it here? I would greatly
appreciate such help.

I have a Gretsch G5135CVT-PS, so I'm not exactly sure if the Signature guitar and the normal guitar have the same dimensions, but the PS version is 1.25 inches thick. Great guitar to be inspired by.