Hi Gill Cook, I have had a look into the ServiceMax help files that I think you have been looking at. I do not think from looking at them that ServiceMax support a visualforce page on Work Order Details.
They support a wizard component on a standard salesforce page layout. If it is for a custom object then you can create a visualforce component for it but I believe that is for objects outside of the ServiceMax package.
So I am looking to understand more of what your use case is here. You should be able to add a wizard for work details to your standard salesforce page layout for work details. Or are you looking for something different?
~If my post was useful, please give me a thumbs up! Mark correct answers as 'solutions' so we can all find answers faster!~