Go to Menards and buy a dremel kit for $9.99.
IU can't find the one I use anymore, but here is a similar one:
http://www.menards.com/main/tools-hardw … -10099.htm

Cyt yourself a rectangle, and then shape it with one of the filing tools. You do not need a perfect trapezoid though, if you cover the hole with the metal plate on your DB-25.

Yah I already have a rotary tool and cutting bits I'll give it a go. Thank you guys!

Cyt yourself a rectangle, and then shape it with one of the filing tools. You do not need a perfect trapezoid though, if you cover the hole with the metal plate on your DB-25.

Awkward holes and filing are made much easier with a dremel (or similar "rotary hobby tool") - just make the hole too small to begin, and "stretch" it out as needs with filing bit.

I take it you're going AC adapter only on this DMG?

Nope. I'm gonna put this lipo cell instead. It fits perfectly the battery compartment so I can remove metal springs and this will give enough space for DB connector

I take it you're going AC adapter only on this DMG?

So I wanted to make all the mods for DMG in a separate box and plug it to the DMG via DB-15 or 9. I want to put it to the bottom of the back plate. But cutting a god trapezoidal hole there appears tricky because you basically have to cut 2 layers of plastic - one the actual shell and the other is battery compartment.

My strategy would be making a rough hole first and then file down the edges. This is gonna be a hassle. So I wonder how would someone more experienced in it go about doing this. Thanks!