After cutting out the old step with the plasma cutter I got the replacement pressed and fitted now.
The next part of the steps will be made from wood and will be on the inside of the wall. The outside (cavity side) of the wall will attach to the face of the lower section of the steps.
Today the show tray finally came . I got the "key hole" cut out for the shower waste trap but there was part of the central beam of the boat in the way. How else could this be cut out in a few minutes without setting fire to the wood floor?
I love my plasma cutter :-)