How to build XP Embedded?

Hi – we build gaming machines here, many of which contain ruggedised PC’s
running XP Embedded. We’re now upgrading our hardware, and my employer is
willing to let me have several unused motherboards for very little.

The boards have XP Embedded licences and COA with them, and I’d like to
build them into PC’s, but the Embedded build we use is pretty minimal, so I’d
like to put full XP Pro on them. If this is legit (my very limited
understanding is that XPe can be built pretty much any way you like, up to a
full XP Pro build), any tips as to how I might go about preparing an image or
install CD?

More of a hobby, ie for learning, than anything else really...

Thanks a lot