These is a sort of a guide for making a side panel window. I know most of you already know how to do these but here it is anyway. To those who already know how to do these, just ignore but kato wala pa, I hope you will learn something and will try it out for yourselves.
I moded the side panel window of the coolermaster CM 690. Total cost for these mod is 300. P250 for the rubber molding @ P50 per foot (I used 5 feet) and P50 for the glass window.
Tools needed:
1. Handsaw
2. Ruler/tape measure
3. Ballpen
4. Muscles(for using the handsaw)
First off, prepping.

Cover the side panel with masking tape para di ma scratch and para pud ma layout nimo ang imo window. Make your widow layout to the size of your choice but make sure there is enough space on all sides para pwede pa gihapon ma close imo side panel. Dont cut too much especially near the rear portion kay basin di na masira imo side panel. Rule of the thumb: "MEASURE TWICE AND CUT ONCE"
Cutting.

Here is the fun part, dont worry about the sweat dripping to your side panel.

If you have power tools, much better. But I prefer the manual, para ma exercise pud ta and mas ma control nimo ang cut. Be sure to follow the line. Its hard to undo these if you get it wrong. If your side panel has no holes, you could use a chisel (tigib) to make a small hole for the blade of the hacksaw to go through. Make sure to make the first hole inside and make you way up outside to the layout. Kung ma sud na ang hacksaw, dali ra man i manipulate kung asa padung imo cut.
Finished product after cutting.

Clean cut!
Next, put the rubber moulding. You can buy this moulding at CarTruck Center in SM, there are different color choices, black, checkered or siliver, I chose silver kay naa man pud silver lines ang CM690 to match.

Close up
Heres the precut window I bought, you could also choose different colors and tints, glass or acrylic. I chose smoked glass. I prefer glass kay mas tina-aw and mas lisod i scratch.

These is how it would look like after.
Next, put double side tapes on the inside. Make it two layers of double sided tape kay kung one layer ra, maglisod ug abot ang glass kay baga man ang moulding.
And the end results.

Nice eh? I think it looks sweet.