Unfortunately, there is not an easier way to do it than the process of modifying a copy of the php.ini and using it with your own instance of php.cgi as described in the wiki. There are reasons why DH sets the settings the way they have, and changing these settings can have a myriad of effects on programs running on the server. You really need to understand what those effects are, and how they could impact others on your server before you change them, or you could expose others that share your server to risks.
The only other real way to do it would be to completely install your own copy of PHP (described in the wiki)- but you will probably find that to be even more difficult than the described php.ini “mod”.
You can get a copy of the php.ini to your computer via ftp by copying the appropriate php.ini for the version of php that you are running from it’s location on Dreamhost to a directory in your space (see the “cp” commands in the wiki article). Once you have done that, just download it from there.
Assuming that the point of doing this is to use your own php.ini as described in the wiki article, doing this won’t really solve your problem; if you do that and replace the php.ini in your cgi-bin with the edited version, it will only retain your change until you next “get” the copies of php.cgi and php.ini from their “normal” location on dreamhost (the next time the update-php.sh script runs, via the cron you set up to keep your copies “up to date” per the wiki.)
It is important to regularly get the “updated” version to protect others on your shared server from potential exploits - when DH updates, you should update.
The real solution is to follow the wiki carefully, adding the appropriate “substitution” regular expression in the perl script to change the “allow_call_time_pass_reference” to “on” in a manner similar to the way the example in the wiki used a substitution regex to modify the max_upload setting.
The wiki only mentions the max_post and max_upload_size, but this forum thread not only talks about the whole process, it also supplies example code as it relates to the register_globals setting; you just need to modify that to make it change allow_call_time_pass_reference instead .
It is not the easiest thing to do, but it is also not the hardest. That thread resulted in a new user accomplishing a similar modification of a different setting; comparing that thread with the wiki article ought to set you on the right path.