Well, I just did a write up of our 9500 GMC Firetruck with the 637.
Clicked the wrong button and it was gone.
So here are pictures of ours and the engine runs really smooth.
http://s893.photobucket.com/user/2-T...?sort=3&page=1
I have more pictures of the 637 somewhere and may look latter.
Here are some pictures of the 65 1-Ton I acquired a few weeks ago.
It has the 292 six in it.
http://s893.photobucket.com/user/2-T...?sort=3&page=1
Don