I've been working on the house all day and am starting to feel like I am getting somewhere. I also asked DH to take me to the DIY store this morning where I picked up a sheet of 4mm MDF for my replacement pieces, and some 15x21mm pine batten for the foundation.
I am tinkering and tweaking as I go along, so it is going to be hard to blog this in a logical order. I don't know if anyone else will ever want to do a similar kitbash, but hopefully if I try to record my decisions and learnings, it will help out someone else.
A word about tools: I do not have a massive tool shop but the Greenleaf plywood is so thin that you don't really need major power tools. For small cuts such as trimming a tab, I am using my wood-cutting shears. For longer cuts with the grain, I find I can usually cut through just by repeatedly running a Stanley knife along a metal ruler, cutting a little bit more each time. This doesn't work very well across the grain, so I cut partway through with the knife, then finish off with the feeble little scroll saw on my Unimat (a toy-like power tool available from Hobby's). For cutting new slots, I drill out the slot and tidy up with the Unimat or a Stanley knife.
Removal of bay windows: I realised last night that I won't be using any of the bay windows, so I cut off the bay window protrusions on all floors, just leaving a little tab the thickness of the plywood. The tab will fit into the horizontal slots on the vertical pieces so that the floors are still supported. I trimmed the left wall completely flush with the side of the porch, creating two new tabs as I cut, because the Pickett Hill house (PH from now on) has a flat left wall with no bay.
The continuing saga of the staircase: I spent some time last night playing with the staircase positioning once the glue had dried on the treads and risers. I've come to the conclusion that the PH is a little bit longer along both sides of the 'L' shape. That's why the PH has more room for its staircase, and why the PH dining room extends further forward. I am not going to contemplate trying to lengthen my Fairfield, so after trying out various options, I have decided to reverse the staircase. By reversing the staircase (stairs facing the back), I can cut off the banisters built into the centre wall and open up that archway for a similar effect to the PH. The stairs will protrude slightly into the smaller archway on the right (looking from the back) which I widened as much as I could (about 1/4"). I cut both archways to be a little higher and squared them off. I think that I can now use the staircase wall by also reversing it, but I'm not sure about positioning a new door for the boy's bedroom. I still want to cut back the middle floor for a balcony-effect similar to the PH, but I need to leave room for the stairs and the bedroom door.