Figure out which drivers you want and copy the specific driver pack folders containing the drivers you require from the full packs to your 3rd party driver pack. (copy only the folders with the *.INF files that contain your systems HWID's) then don't use/select the full packs provided here use your custom third party pack instead. you should easily be able to stay under the 4096 limit. helpful?
however if you don't use sysprep this becomes a non issue - That is what I and siginet were trying to get you to understand.
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My first computer was a dumb terminal + mainframe over 38 years ago. I was old school before they built the school.
I won't even begin to give you my full background. Suffice it to say have clients that are 50+ locations spread over multiple states and others that are international. I'm not some script kiddie, I have more than just a clue....
WPI is very easy to edit (kill the installation display or just the abort button and set the selection timeout to 1 sec or bypass it) but moreover it is a learning tool. It will open doors showing you how other people have already figured out how to automate the install of almost any software program you can think of. You can just get the command line switches from the forums and then write your own scripts and not even use the wpi interface if you don't want. just use the examples and not have to reinvent the wheel.
you could use RIS with my recomended combo for non DVD stations or even for DVD Stations given the fact that network transfer rates could in the right setup blow away DVD transfer rates, and I always carry my external usb dvd with me for emergency.
perhaps a little more research using my advise since this discussion is way beyond the scope of this forum....