Hi! I'm actually getting ready to do the same installation on my '54. My problem is that mine did not have the metal bow you speak of (I'm going to order one soon). But I did read some historical posts here, and my understanding is this: The bow's cross-section is an "S" shape, giving it an upper and lower groove. The rear headliner should go into the lower groove in the bow, and the front headliner should slide into the upper groove of the bow. Perhaps someone else can confirm what I've researched. Hope this helps!