Windows Universal Installer, Reatil & OEM question

Hello, I've read lots of posts on this and other forums, about how to create a universal installer, and am happy with the ei.cfg method, but I wonder if it can go further...

I'm only really interested in 64-bit so don't need to extract and use WAIK.

I need to sometimes install as OEM and sometimes as RETAIL (because I believe an OEM key won't activate a RETAIL installation - is that correct?). Is it possible to do this on one install source?

Many thanks,
Steve

The retail and factory/builder's OEM installation media have been the same since XP.

It is the key which determines which version will activate.

No in that case where you have a different version than Home Premium so must either download a new Home Premium ISO or extract the ISO file from disk using ImgBurn, delete the ei.cfg file with eicfg removal tool which will unlock all versions, then burn to disk again. Then choose the licensed version during install.
Windows 7 Direct Download Links

I think Brian thought you were pulling my leg. But it's a legit question anyway since Vista did let you activate any version from the install disk depending upon which key you have.