Craig, I am going off of my Ryobi 31cc, which I converted to glow. The setup as shown in the picture (minus the spinner) is just under 3lbs, according to my 5lbs postal scale. The CH Ignition module I have for it weighs less than 4 Oz. If I use a light weight battery pack, I can fairly easily stay under 3-1/2 lbs.

The engine in the picture also has a lot of the unnecessary bosses and appendages ground off. I could probably take off another 1-2 Oz. if I really wanted to. Also, the B&B muffler stingers most likely can be shortened. Plus it really only needs one stinger anyway. It's substantially quiter with one pipe blocked off and I only saw 100-200 rpm drop.