240D Valve Adjust and Retorque of head

[Fisherman]

Once again I need help...
I have the CD coming but need to do some work today on the car.

It appears I have the 616 engine according to my manual? 1975 240D 115 body. Does this sound right or could it be the 615 engine or does it make a difference anyway?

Anyway, I have two settings to use .10 and .30. The .10 is for Intakes? I have read in great depth all of the threads (about 6 hours worth) on valve adjustments so I believe I have my plan well thought through on this.
The image attached is from my valve cover and seems to indicate two different settings for the valves based on engine temp. It seems odd though because the higher temp indicates a wider gap? Shouldn't this be reversed due to expansion of the valves when warmer?

Secondly, while I am in, I was thinking of retorquing the head as I have a minor water leak at #4. My questions are:
1. Does it make sense to try to retorque the head?
2. Will the bolts be so set already that I may fail miserably, i.e. snap a bolt or at least not get the correct setting due to the bolts being "locked" in place over time? Perhaps backing them first a quarter turn and then retightening?
3. What is the torque setting for these bolts?
4. Is there a pattern used for loosening and then retorquing?
5. I believe they are the hex key bolts that I see, what size are these?

Sorry for all the questions but I'd like to do this right the first time.