My Full Spectrum 40W hobby laser came with a beam combiner for the red dot aiming, but then I read that the combiner lens can reduce the power of the laser up to 20%. I don't know how accurate that it is, but it makes sense that some of the power would be lost with it, so I went with option #2 instead. Based on Glenn's design here (
http://glennlangton.blogspot.com/2011/08/laser-cutter-cross-hair-guide-for-under.html). However, I made a couple modifications. First, I modified the SVG to hold 2 of the Deal Extreme lasers, instead of reusing the original laser. That was a quick copy and paste of the arm section. Second, I added a line not all the way across the connected side of the arm so that I could easy bend the arms with heat.
The red line lasers were horribly out of focus. So, I laser cut a small circle with a slit (0.312" diameter) of the top of a post-it, and stuck this over the Fresnel lens on the inside of the laser. The result was a much more crisp line. To aim the lasers, I used the machine to vector two lines onto a piece of wood, then aligned the lasers to these lines. A couple drops of super glue went onto the lasers after they were aimed to help hold them tight.
The photos below, the red lines appear fuzzier than they really are, the phone's camera was too sensitive to the red light. I have a little cleanup to do still on the wiring.
