Head test methods...

[Endust]

What would be a good way to test the head for valve guide wear on a 300D non-turbo. I cant tell if I have bad valve seals, worn guides or both. Is the only good way to pull the head apart and wiggle the valve while its off its seat? Would head probelms contribute to very oily blowby? I plan on doing a compression test soon but I can easily start this car in when its in the 20's with no block heater. That makes me think my oil consumption is in the head. Any tips??