Software Deployment

Hello,
Can someone tell me what is the correct way to install files in the GAC_MSIL folder.

I found this:
---------------------------
Anything captured in GAC Native images folder- they are dot assemblies registered with ngen.exe - native imgaes are created for faster execution of assemblies. One needs to delete these files from captured wsi and use ngen in custom action to create native images for these assemblies.
-------------------
But i don't understand this fully.
Do i need to put the files in a folder under the 'program files' and then use the 'Generate native-code version during installation' ?? or do i need to put them in the GAC folder and use the 'Generate native-code' from there?

I;m using wise package studio...

Thanks a lot