In my opinion a sign like this would never be used inside. First, it's too big, and secondly they went to all the expense of making it porcelain so that it would stand the test of time outside. All of the Buick signs like this I have owned had holes in them towards the top where the Valve in Head sign would mount. Could be left side, right side (either side of a double sided sign like Dave pictured above) or even center (single sided wall mounted sign with Valve in Head in center). Look for holes and I would be very surprised if you don't see 2 on the same horizontal line with one or two centered below it. Good looking sign at a great price.
