Don,
There are a couple vintage snap on units on ebay right now.
http://motors.shop.ebay.com/i.html?...0.l1313&_odkw=PROTO&_osacat=6028
If the link doesn't work, I just searched for "valve adjusting tool"


1953 Chevrolet 3600
Fried Green T'mater (Vern)
In the Stovebolt Gallery
Caution: Political Statement
Man who runs in front of car gets tired, man who runs behind car gets exhausted.