I may be getting a Zone VI type 2 enlarger (type 2 is the one with two posts sticking out of the head, right). My intention would be to use it exclusively for 6x17 enlarging. Does this head have adjustments for contrast grade? The compensating timer is included, but I don't see any way to change the contrast grades. Is there a power supply to worry about? I assume that is handled either in the head or in the timer. Replacement bulbs - are they available anywhere? This has the 44" column - what would the maximum print size be from a 6x17 negative? And since this is likely a factor of the enlarging lens, what lens would you use? Is that enough questions for now? I guess so.