Cylinder Head Temp - How hot is too hot?

[Brad Baker <bbaker@xxxxxxxxxxxx>]

I took my (new to me) 68 Westy on its maiden camping
trip this weekend.  Prior to the trip, I installed a
cylinder head temp gauge.  What is the standard temp
range for my engine?  Below is a list of my observed
temps.  Am I running too hot?  If so, what should I
look for in order to get the temps down?

Coasting down long hills ~300
Idling ~325
Std In Town Driving ~350
Steep Long Hills at speed ~380

I live in Colorado, so avoiding steep long hills will
be impossible...

p.s.  The bus was great for camping and did pretty
well on the "jeep trail" that we took it on to get to
our rock climbing destination.  

Thanks,
Brad Baker