Best option tying in to cast iron plumbing

[MatthewaveryUSA]

Hi,
I'm moving a bathroom and need to tie the sewage to my soil stack. I see a few options:
1) cut the horizontal iron and use some no-hub couples and a san-tee. My concern here is I have no clue how this stack is supported and I don't want things to settle the wrong way.
2) cut vertically and add a combo wye. This seems like the safest bet although it'll be a tight fit on the right.
3) remove the cast iron cleanout and use a donut + combo wye. I would need to run about 4-5 feet of horizontal pvc parallel to the current stack and add a PVC cleanout. This looks like the most elegant option, but googling for how to do it involved flames and molten lead -- can I just use a drill/chisel/hammer/plyers?

Which one would you recommend I do?

Thanks! -Matt

 

[John Gayewski]

Option 1 is out and not legal.

Option 2 is the only real option.

Some doughnuts don't exist and even if you found one it could still be the wrong one. I talked to fernco directly and they sent me the wrong doughnut. Even with precise measurements.