Idle 1800 - 2000
Full Throttle 3700 - 3900
Valve Settings - cold
Intake .008 - .012
Exhaust .010 - .014
Point Gap .020
Camshaft Timing
Align Marks on the crankshaft and camshaft gears (cam lobe will be pointing toward crankshaft, and both valves will be closed).
Piston Rings
End Gap .007-.017
Side Play - Top ring .0015-.0030 / Others .0015-.0025
This is the fuel valve used on engines with the rubber grommet in the fuel tank. Early versions of this part had a mesh screen at the inlet. Later versions had the porous sintered metal filter as shown 
New head gaskets are now available from Doug Bauman. The gasket will fit all the REO engines 1954 and prior with 2" pistons. The gasket has a steel mesh core and is the type of material used for automotive turbochargers and exhaust manifolds. You can contact Doug at : baumandg@prtcnet.com
Also check out Doug's REO website: