How to find all PHP files/dirs to uninstall from Linux

I compiled PHP with support for the thttpd module and now I need to remove PHP and thttpd and reinstall PHP with Apache module support instead. How can I find the directories and files that were created when PHP was installed? Do I have to decipher a 'make install' file or is there an easier way i.e. an install log file somewhere (that would be great!) ? I've never previously had to remove a 'make' installed Linux program (only Slackware packages), so my Newbieness must be obvious to some of you :) I like to have as clean an OS as possible so I'm not keen to just recompile PHP with Apache module support and leave redundant PHP thttpd related files lying around, even if this course of action is possible. Leaving redundant files lying around reminds me too much of Windows and it's registry!! :-) FYI, I am running Slackware 7.1 Thanks, Scrumpy