Ouch! It requires recompiling Apache.
Are you sure it requires recompiling? On most distros it should be a default module. In Debian I found it precompiled at: /usr/lib/apache2/modules/mod_suexec.so
Apache's docs are distro-agnostic and harken back to the days when every howto told you how to patch and recompile the kernel. (Those things persisted long after the modular kernel made it unnecessary.)
Aha! The plot thickens. Thank you, Jonathan. Indeed, I read the Apache docs and bailed on the idea because they mentioned recompiling. In fact, the module exists, at the same location you described, on a Gentoo box.
I think I can tinker with Kyle's proposal after all, as it appears that mod_suexec is ubiquitous.
Thank you, all who responded. I learned a lot, and now have three valid solutions to the problem.
-Jared