The 37's are metal. It attaches to the door post with a "pin" that drops through the "bracket" at the end of the door check. The door check goes in from the inside of the door. When you close it the door check goes back inside the door.
Sorry I don't have a pic of it but hope this helps..... Note, do you have a shop manual for the 37??
I'm not sure if it shows it or not but you can check at the online manuals.
http://chevy.oldcarmanualproject.com/Welcome to the Stovebolt. Post us a pic of your truck when you can and drop by the welcome Centre and tell us a little about yourself.
