Fire up a shell and follow these steps (these command are from http://wiki.dreamhost.com/Bugzilla) in the directory of the domain you want to install Bugzilla in.

mkdir bugs
cd bugs
wget http://ftp.mozilla.org/pub/mozilla.org/webtools/bugzilla-STABLE.tar.gz
tar zxf bugzilla-STABLE.tar.gz
rm bugzilla-STABLE.tar.gz
mv bugzilla*/* .

Next, follow setups 6, 7, 8 and 9 from the Bugzilla Dreamhost wiki.

Now you will need to manually install Module::Build and DateTime::Locale for Bugzilla to work. To do this, first get the latest CPAN download links for the modules.

For Module::Build, you’ll find the download link here: http://search.cpan.org/~kwilliams/Module-Build/
For DateTime::Locale, you’ll find the download at: http://search.cpan.org/~drolsky/DateTime-Locale-0.43/

I’ve used the latest available builds at the time of this writing for the example below. Next, follow these steps in the Bugzilla installation directory:

mkdir tmp
cd tmp
PERL5LIB=/full-path-to-bugzilla-install-dir/lib
export PERL5LIB
wget http://search.cpan.org/CPAN/authors/id/K/KW/KWILLIAMS/Module-Build-0.31.tar.gz
tar xzf Module-Build-0.31.tar.gz
cd Module-Build-0.31
perl Makefile.pl
make
make test
make install
cd ..
rm -rf Module-Build*

# To install DateTime::Locale
wget http://search.cpan.org/CPAN/authors/id/D/DR/DROLSKY/DateTime-Locale-0.43.tar.gz
tar zxf DateTime-Locale-0.43.tar.gz
cd DateTime-Locale-0.43
perl Makefile.pl
make
make test
make install
cd ../..
rm -rf tmp

Re-run ./checksetup.pl and then fix permissions as in the Dreamhost Bugzilla wiki page:

for i in docs graphs images js skins; do find $i -type d -exec chmod o+rx {} \; ; done
for i in jpg gif css js png html rdf xul; do find . -name \*.$i -exec chmod o+r {} \; ; done
find . -name .htaccess -exec chmod o+r {} \;
chmod o+x . data data/webdot

You should now have a working Bugzilla installation at yourdomain.com/bugs.