Okay, it looks like there is remnant of old code here which may be why many people cannot get GD to work.
I had to do the following in order to get this to work...
plotimage.php is still calling up plotconf.inc and plotip.inc or whatever the OLD files are named. It should be changed to include ipconf.inc and ipplot.inc.
Also, in
ipconf.inc include("./iplocation/translate.inc"); should be changed to just include("translate.inc") since it exists in the same directory.
Made those two changes and GD works great for me now!
Wonderful hack! My paranoid admins absolutely love it.