Hello. New to the forum and hope to get some advice. Just bought a 68 Camaro with a late 70's chev 350. I have the cam card for the cam (with solid lifters) but it is not clear if the lash settings are for a hot or cold engine. Attached is a pic of the card. What do you think?

 

I have always adjusted mine hot while running.
they make clips that go over the rockers to reduce oil spray while running. you can also get the engine up to temperature and shut it off and adjust.
my opinion only, running is better for adjustment

 

I've never done solids with the engine running, I do an initial adjustment cold being sure not to be too tight, a little loose is fine for initial cold adjustment. Solids will let you know if they are too loose because they make a lot of noise but as long as you don't run it hard they'll be fine, too tight and you'll bend pushrods etc.
Once she's warmed up re-adjust to specs then listen to them ( those aforementioned clips come in handy, extra valve covers with the tops cut out are nice to have too so oil doesn't get all over.
I have tweaked a loose one or two just a bit with it running and warm if they're noisy. If you hear one that sounds loose you can find it with a little pressure on the rockers one at a time using a piece of wood until you hear a difference in one.
I had a 427 with solids I hot-rodded the hell out of, I was adjusting lifters a lot. lol Every weekend I'd re-adjust the lifters and the dual points in the full manual advance Accell dizzy and the timing advance then go out and kill Mustangs and TransAms with my '69 Camaro ha ha ha.

 

Industry standard was 'HOT' lash setting.
You can adjust with them hot and not running.
Bring engine to hot temp by driving.
Remove valve covers.
You can remove spark plugs in making engine easier for manually turning, or use a remote starter switch and bump starter.
Use EOIC method - Exhaust Opening - adjust intake valve; Intake Closing, adjust exhaust valve on same cylinder.
Follow firing order, mark rockers adjusted with chalk, one can lose where the adjustment was at with outside interference.

 

That remote switch really helps, forgot all about that and I bought one way back in the day just for this job. The big block was super easy to pull the plugs out of so I did that too.

 

Cold settings: iron block & heads .002 looser, iron block & alum heads .006 tighter, alum block & heads .012 tighter.
I set #1 cylinder exhaust valve then the intake valve then rotate to TDC and check the lash at TDC (usually .001 tighter on intake and .002 tighter on exhaust). I then rotate the engine clockwise 90 degrees at the crank and set #8 cylinder valves at the same TDC lash as #1, then another 90 degrees to the next cylinder in the firing order and so on.