Currently in the process of rebuilding a Magnatone 150 but I'm running into a bit of a problem in regards to the speaker baffle. In doesn't have one. So I need to build one from scratch using birch ply. Has anyone ever owned a 150, 160 or 180 model? And if so could you tell me if it was a 3/4" or 1/2". 3/4" seems like a good fit (grill cloth would rest directly on the wood face). Then again, 1/2" would work as well as long as there were shims to the face (which adds space between the face and the grill cloth).