Well, I just posted, or thought I did! And it is lost somewhere in cyber space!
Parker, that is an awesome looking system, and I’ll bet your grand parents are grateful, and proud of you for getting it for them. As I was saying in my lost post, about a hundred years ago when I was a rep for several component system manufacturers, I could have helped you with the problem. [unfortunately that was in the old days when they used vinyl records and weighted turntables, and tuned and ported speakers were just coming out. Everyone was convinced that a large open reel tape system was the ultimate in sound fidelity.] Sorry I can’t help you with the problem, but if you haven’t already looked, try
this linkHTH
In the mean time, I will see what else I can dig up for your.