Rebuild kernel for old pc

Hi everyone. I want to build a bzImage and its modules for and old pc which has slackware 14.2. I'd like to slim it as much as I can. My question is, may I build them using another slack 14.2 much faster pc? I tried once, but copying modules folder spammed "files link error" message. I succesfully loaded the new bzImage into the oldy with some troubles, maybe due to bad .config uncheck options.

Is it a matter of copy/paste thing? Or there is something extra I'm missing?

Thank you very much!