Classic/Antique Car Repair: I have a part i dont know what it is, vacuum gauge, gm part number

Question
QUESTION: I am going to send a picture in html and hopefully it will come up as a picture. If that doesn't work can you send me an email I can send you picture<br><img src="http://i1184.photobucket.com/albums/z323/gearheadsgear/mis%20parts/IMG751.jpg" border="0" alt=" photo IMG751.jpg"/>

ANSWER: It looks very much like the pod that was on the hood in front of the driver on some models of Pontiac performance cars in the mid sixties to house the tachometer. Are there numbers cast into the bottom side of this? Also can you send me the rest of the dimensions as well as the numbers? Then we can research it further. Also what is it made of? Let me know.

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QUESTION: It's not for a Judge or any Pontiac I have seen so far. The only number's it has on the under side are inside of what I will call circles one is 87 and the other is 86. It is made of cast aluminum. I will send more pictures I have had this thing for years. I am wanting to use it on My 1960 El Camino. I thought it was off a Judge however, it's not . I am not sure what I will put inside it if I cant figure it out . I was just hoping someone could help me so I didn't spend ton's of hours fabricating something to later find out I could have gone to part house and for 20.00 put the part that it was made for that is cooler than what I made. Thanks again for your help................................"http://i1184.photobucket.com/albums/z323/gearheadsgear/mis%20parts/IMG753.jpg" border="0" alt=" photo IMG753.jpg"/><img src="http://i1184.photobucket.com/albums/z323/gearheadsgear/mis%20parts/IMG752.jpg" border="0" alt=" photo IMG752.jpg"/><img src="http://i1184.photobucket.com/albums/z323/gearheadsgear/mis%20parts/IMG756.jpg" border="0" alt=" photo IMG756.jpg"/><img src="http://i1184.photobucket.com/albums/z323/gearheadsgear/mis%20parts/IMG755.jpg" border="0" alt=" photo IMG755.jpg"/><img src="http://i1184.photobucket.com/albums/z323/gearheadsgear/mis%20parts/005.jpg" border="0" alt=" photo 005.jpg"/>

Answer
I have several other thoughts about this piece. There was a Pontiac in the late 50's that had a radio speaker mounted under the center of the dash in a pod very much like this. It had a chrome mesh grille on it. There was also a GM car that had a vacuum gauge mounted in a pod very much like this on the hood in front of the driver. However all that said if it was a GM part from that period it should have a GM part number cast into the under side.