Do it yourself, replace the headlight assembly on your Pontiac Montana made in the years 1999, 2000, 2001, 2002, 2003, 2004 and 2005. For this repair you will not require tools or skills. The repair process is very simple and it should not take you more than 10 minutes. In some cases you may need a pair of pliers, if you encounter problems on the way (rusty or damaged components, nuts that do not come out by hand, etc.).
At the beginning, open the hood of your car and go to the headlight that you need to replace. You will notice three plastic nuts holding the assembly, that you can remove by hand (see picture below). There are no tools needed, but if one of these nuts is very rusty or is more than finger tight, you might consider using a pair of pliers.
So, remove the two wing nuts holding the main light and the nut holding the blinker, pull the assemblies out and unplug their harnesses (as shown in the next image for the main piece).
At this point you can work to install the replacements. You can service the bulbs easily by turning their sockets clockwise or counterclockwise, by the case. Connect the harnesses back and install the new headlights, paying attention to the plastic pegs that have to enter into their wholes before fixing the assemblies (marked with blue arrows in the image above for the main light). Tighten the wing nuts and this is it. These are the steps you have to follow if you need to replace the headlight assembly on your Pontiac Montana made between the years 1999 and 2005.