Alas someone who knows a thing or two!

Thank you for that. I'm no expert but can provide most of that information:

We are having all new bearings (+big end +little end) in the engine, new piston. We are not going to be changing the piston every few hours. The bike will be ridden as a weekend toy but will be maintained well.

Any idea of what the squish angle and width should be? - bearing in mind this isn't a race bike and absolute performance is not required. Just want something that is correct and going to work well.

What compression ratio should we be aiming for, again bearing the above in mind.

I just want decent figures that we can aim for  - something we can give the engine builder and have confidence in saying.

Want this thing to last.

Thanks for your help.