On 09/08/2019 22:48, John Rumm wrote:
I would be tempted to scribe a line and trim out at least some of the
error. The sit it on a bed of plumber's gold. Once that has gone off, a
bean of more plumber's gold round the perimeter to make a water tight
seal to the floor.

I am in the 1st instance going to try the UPVC trim I have to level it
and see how it looks, then probably scribe/trim as my second option.

Using the UPVC trim as a first choice is less destructive should it not
look good.