Hello, Before posting this I've searched here without success, so I turn to you. I want to install a Hipshot Extender on my new Gibson Thunderbird IV, but do they make one for the Tbird? I didn't see any on their website. Will one of the few "generic" Extenders do the job, such as the HE6Y or GB7? Most appreciative if one/some of you guys can steer me in the proper direction.