water pump/ distributor removal

im working on my 72 350sl water pump and im stuck at the point where i need to pull the distributor to pull that last bolt. my haynes manual isnt helpful at all as to how to remove the dist., it tells me to remove the clamp bolt but offers no pic as to what this bolt is. im assuming it is the bolt in the slot to adjust the dist, but this didnt work too well. is this the wrong bolt, is there another bolt i should be loosening? i felt all over for something else but cant seem to find anything. if i am on the right bolt why wont the dist pull out ? it wont even turn in its adjustment slot, is it just old and set in its ways and doesnt wanna come out or am i going about this the wrong way? please help
thanks in advance, michael