Any valve lash advice from the gurus?

If this is the only thing you learn how to do on that Slant six you got about three-quarters of the tune up down packed! Every time I've had one of these I've done a valve adjustment and had great results because nobody seems to do them. They need them.
I personally recommend the very first time you do this not to have the motor running! This is your first time and you already sound a bit intimidated and having moving parts and noises going on while you're trying to do something doesn't sound like a good idea. I've done this several times and never once have done it running not to say that's not a better way or anything but it just seems safe. Also if you're comfortable with pulling all your plugs out and knowing your firing order then it would be easy to turn the motor over with them out. My-2