Thanks for the replies.
JMirisola - As far as I'm aware, alternate positions only works with parts in an assembly rather than different configurations of a single part.
As suggested I'll go with a sketch that can be shown in the drawing view, just thought I'd check in case there was a SW...
There is a function in SolidWorks to show alternative part positions in a drawing, with the alternative position in dashed lines.
I would like to do a similar thing, but with a modified part (ie the original part is shown as dashed and the modified version solid, with the ability to dimension...