WC waste pipe slope wrong way

I've taken out a 1980s toilet (almost pink, maybe 'flesh' colour, delightful) and am putting a new white one in the same spot. The waste pipe needs to be slightly lower in order to connect to the new one, and this now means the soil pipe is going to briefly slope the wrong way. I am wondering if I can get away with it, because the thought of going near the soil stack - cast iron, hidden inside the wall - does not appeal! So I'm stuck with this pipe going through the wall in the place that it does. Goodness knows how the current plastic fitting connects to the metal pipe.

There is only a 9 inch stretch of pipe that will be 'uphill' until it gets to the elbow. The rise is about 1 inch. Has anyone has a similar compromise and found it to cope? I know the water in the pan will be 1 inch deeper.

Or will it be a disaster? I could probably sit the toilet on a 1 inch block of wood if i had to, but that will look rubbish.

Photo tries to show the view from the floor. Thanks everyone.

Set the toilet on a plinth

It wont work, you are asking to defy the Laws of Gravity. Either raise pan on a Plinth as suggested or lower the Soil pipe.

Not wood plinth .

On the other side of the wall I have hacked a hole to look at the soil stack. It is cast iron below, and then the white collar at the bottom of this photo joins it to the plastic fitting. I don't see how I can lower it, even if I didn't have the second toilet (the one on the left) to worry about too!

Get a loo with the outlet at the same height as the old one?

(In my naivety I guessed that all toilets had their outlet at the same standard height, but this seems to not be the case because you are not the first to ask a question like this here. Experts, how much variation is there? Has the standard height varied over the years, or something?)

Measure the height of the centre on the outflow pipe at the wall and see if you can get a pan with the spigot at least at that height, if it isn't overly high.