Did you rebuild your 235?
The reason that I ask, is that depending on the year and if it has been rebuilt or worked on, a lot of 235s in the states have hydraulic lifters even if they did to begin life with them. So as a starting point knowing that you have solid lifters is key because they are adjusted completely differently from the solid lifters.
While a lot of people with many years of experience feel that you can adjust the valves cold vs. hot while the manuals say it must be done hot to get best performance. I seen old line Chevy mechanics do it by ear. My experience with the 216s and now 235 and 261 would say it depended on which truck, fuel and how hard you drive. The HUP with an engine that you actually used the gas pedal to control the speed; you could probably do the valve adjustment cold and not have any problems. On the C60 with the engine working a lot harder I don’t think so.
The trade offs on getting the adjustment correct are, too much clearance more valve noise and less power as the valves don't open as soon or as far, and the engine can't breath as well. Too little clearance and a valve will probably burn or you will get back firing in the intake.
Anyway you look at it doing a valve adjustment job on a CMP is difficult. First off it really takes a long time for the engine to actually equalize. Idling the engine alone just won't do it so if driving the truck for half and hour is not an option then I agree with Keith Orpin set the engine completely cold. By the way Keith your tip about the order is interesting; I've printed it out to try in the shop the next time I adjust valves. One tip I would suggest is that you attach a vacuum gage to the engine manifold as you will see quite a difference as you get the valves dialed in. One thing for sure you will be able to spot real quick is any valves that are not closing completely. Strangely enough you can spot a burned or open exhaust valve as a flick in the vacuum gage on the manifold.
I just pulled the Chevy Manuals US car truck1939, Canadian Car Truck 1940, MB-C1 1942 and MB-C2 1943 all of them have significantly different information about adjusting the valves. Someplace I remember a manual that listed both cold and hot valve setting I'll try to find that one and then post all the valve adjustment information.
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