Where can I fit basin waste in?

[Cat007077]

Hi novice here!

I’ve plumbed in (thanks to Ian on here) a vanity into a toilet room that never had a vanity basin (59’s they didn’t wash their hands )

Now need to fit the waste. But have read horror stories of plumbing into a cast iron stack!
Unfortunately, I only have a cast iron soil stack or plastic pipe at back of toilet.
I know the pipe under the floor, leading into downstairs toilet, is plastic (as it was replaced years ago).

Please see pics
Where’s best to place to plumb it in?
Many thanks for any advice

 

[CBW]

Could it go on the other side and use a pan connector with waste spigot?

 

[Cat007077]

Good idea .. I thought of that but would place the vanity unit right next to the entry door and would take some negotiating around to get up the get toilet.

 

[Cat007077]

Thought of using this but scared I might crack cast iron pipe drilling it