LinuxQuestions.org - how do i make custom installer

First of all i want to modify my install config so when i check desktop environment it only installes icewm as the wm where are these files located? i cant seem to find them someone should be albe to point me out to the deb files to modify. pleasse no opinionated people im reposting because i need to modify this and only this i do not need a scripting tutorial nor peoples opinions on what i sholud do besides this., this is all i want to change so please NO comments on why what im doing is wrong i do NOT need your opinion on what i should do, only facts. This is what i need, all that i need, and nothing else, if you cant help me then please dont post it makes others that might be able to help me think the problem is already solved. i was thinking it would be in the base-config.deb but i extracted it and examined all the scripts and found nothing relevant.