Shower TMV

After a bit of advice on how to change the shower TMV.

I wish to plasterboard and tile the shower wall. So I have to get previously fitted TMV off.

It is chased into the wall and has copper elbow fittings then into TMV. Which won't be long enough. Copper fittings have grout on too grr

What is the easiest way of doing this, a plumber friend mentioned plastic push fittings. Could I just turn stop tap off take old elbow off then replace with plastic elbow, temporary piece of pipe and stop end.

Any advice would be great. Confidence with plumbing isn't great but I have changed bits and bobs.

 

Any ideas how to get all this old grout off without scoring The pipes.

 

Right managed to get grout off wasn't around the actual joints as I thought it would cause problems

So I'll attach a picture!

Could anyone tell me how I could extend the exsisting pipes out to dry line.

Is it just 15mm short pipe the stop ends.

How do I join it when I remove the TMV as it looks to me as the joint is the TMV if that makes sense

 

Easier to explain with a pic

 

The wall is chased already, maybe looks a bit older cause of grout etc.

But probably will last longer than plastic.

I still have the floor access to the pipes below not screwed down yet.

Could I cut them and run plastic? Just though it was less work take that off did extend pipe. I'm guessing not