Many thanks for the comments, much of what I am doing is trial and error, which is why the main chassis and body parts are all wood at the moment so I can alter them and resolve issues before I cut metal
Currently making a rear axle hanging support pattern so this can be cast as I need to reduce the width of the chassis so the drive chain from the gear box will clear the front mounts - all will become clear in due course once I've built yet another wooden chassis...