Hi Martin,
That's very helpful, thank you. I have modified the drawing I sent you , I actually did it a week ago, but simply have not had the time to slice it and send it over. So my apologies for being somewhat absent over the past week - life has been quite hectic.
To cut a long story short, we put our place on the market (looking for somewhere with a garden), got an offer from someone who wants to move fast, and then needed to find a place. Found one, negotiated etc, offer accepted etc, only to find out today that we've been gazumped.

So the past week has been a bit of a panic of tidying, viewings, searching etc.
I will check my version against your drawing above for wheel clearances etc. My apologies for not seeing your post sooner.
In other (good) news. You'd suggested to Steve in a previous post (which I missed at the time) that he might send some buttons.
Well, like the great man he is - he did just that. I have his 'care package' in front of me now.

I'm pleased to report that he's not gone cheap either, and has sent a rather premium package of chocolate buttons which I am looking forward to consuming very much indeed.

Steve, I haven't sent a 'thank you' yet as I only discovered them yesterday. I thought the package was for my daughter who has gone on holiday so had put the box on her desk. Karen discovered they were addressed to me yesterday - I think she has a good nose for chocolate.
Anyway, with all that said and done, I'll sort the drawings and get them over to you tomorrow afternoon - viewing yet another property in the morning. I can't do it this evening as my brain is fried and sick of the screen, so I'm going to compose myself and re-claibrate whilst making a little more progress with a white metal Ruston Bucyrus 19-RB which I've got on the go.
Sorry for the long-winded excuse, I'll send tangible progress for you (and Steve) tomorrow.
James
p.s. Steve - you're the best.