Rene, this is done in less than a day, trust me! And from some of your posts I have the feeling you do have the skills wink My Mog's got a little more than 15.000km on the clock, so not really that much - and there were quite a few long distance trips that I have done, so too much short distance travel can't be the major reason.
I am considering a professional walnut blasting now that the catch can is installed, just to get it properly cleaned once. Anyway, looking at the intake valves will now become one of my regular inspections.