Changing toilet help - salt glaze waste and clay pipe

Our bathroom suit is ancient, guessing early '70s, and I am in the process of changing it. I have changed the bath and sink which was all straight forward enough (if you class getting a cast iron bath that has been chipped into the wall at both ends straight forward!) but I am having trouble with the toilet.

The problem is the current pan is raised about an inch and a half off the concrete floor sitting on cement and has a horizontal waste exit at the rear which is joined with cement to a clay pipe going into a salt glaze soil stack. How do I get this pan out, how do I then connect a new toilet to the salt glaze soil stack, and what can I do about the inch and a half that the old pan is raised to meet the waste pipe?

I am assuming the only way i get get this pan out is to break the pipe that joins it to the soil stack, but how do I do this without ensuring I don't break the soil stack? Or do I need to somehow leave the joining pipe in place and reconnect to it?

As you can tell, I have not dealt with salt glaze or clay pipes before when it come to soil stacks!

I had thought about just replacing the whole soil stack but it is bricked inside the wall inside and out.

Use an angle grinder to cut the pipe. Be careful not to let any pieces fall down the stack pipe.
What floor are you putting down? And how thick is it?

Are you sure it's salt glazed pipe? Only time that would have been used above ground is for a ground floor bathroom, and even then its usually a socket in the floor. Cast iron or asbestos cement was most commonly used above ground prior to plastic.

I am just guessing on what the soil stack is made of as it looks like its been painted black several times with very think paint. I will check it again.

So I should just cut the pipe with an angle grinder? How do I then connect to it with the new toilet? The new floor going down will be some kind of vinyl tile effect I think, not really helping the height get close to where the current one is.

Need to find out what the pipe is made from first, do not attack with an angle grinder until you've determined it's not asbestos!

Is this an upstairs bathroom? You need to offer the new pan up and see if you can get a fall from the pan outlet to the existing soil, if not it's going to have to be lowered somehow. If you can put up some photo's we may be able to see what you currently have and advise further.

These are the best pictures I can get at the moment as there is a horrible wooden (and tiled) frame around the pipes. I will smash this off soon but don't really want to until I work out what to do.

Sorry the first 2 images should be rotated 90 deg clockwise

Looks like cast iron.

I think it does too, im going to pull all the wood out the way so I can get to it properly. If its iron, can I just break the old joining pipe and connect to it with a new plastic one?

Cut not break look for "Record" or "Ridgid" cast iron cutter hire

+1. Do not try and break it, or you'll end up with more aggro than you ever dreamed possible. Once cut, chamfer any sharp edges and look for a connector than fits inside. Use an extension piece if need be to make up the gap from pipe to pan. Make sure it has a fall in the right direction too!