Oh!! I was, apparently, making this wayyy too complicated. At the head of each page I simply put in:
<base href="http://mydomain.com/projects/customer/" ></base>
And suddenly, all my index.html and about.html links are now going to mydomain.com/projects/customer/index.html etc.
I figure when I move the site to my customer's domain I'll just omit that line from the head of each page (MUCH easier than rewriting all the links!) and all will be well?
Actually, I should probably change it to
<base href="http://mydomain.com/projects/customer" ></base>
with NO trailing slash, and change my index.html links to /index.html, right? Because without a base href all links will try to go to www.customer.comindex, right? Not www.customer.com/index?
Sorry for the crazy newbie questions!! I'm new to moving sites around servers and just trying to make it easier on myself.