Can I move cleanout and wet vent here

[KSdoit]

As shown in the diagram, I have a SoW stack that serves the 1st floor of my two story house. I have 3 SoW stacks in total.

All of my 1st-floor fixtures connected to this SoW stack are true vented (their traps are not shown).

I would like to add in the basement in a finished "craft room", a utility sink (no disposal), and I have the following questions related to my diagram:

1. Can I relocate upwards by 12-24" the current cleanout so that I have room to connect to this SoW stack at the proper slope.
2. Can I connect to this SoW stack and wet vent?
3. If I cannot wet vent, why not?
4. If I cannot wet vent, could I "kitchen island sink" vent?
5. If I cannot do 3 or 4, can I true vent my new craft room sink to the existing true vent at location #2 (the one exposed to me that is servicing the 1st toilet).

Thank you.

 

[Terry]

You can move the cleanout.

The sink downstairs will need venting. Perhaps an AAV is the easy solution.
If you dry vent it, it ties in at 42" above the 1st floor, six inches above the flood level of the highest fixture there.

Wet venting isn't done between floors. It doesn't work.