Very nice, Jim. I got my Perky kit in the mail on Monday. I've gawked at a couple of them, and I'm concerned about the tank. Doesn't seem to be much room in there. What did you use?

Paul, that split construction opens up new possibilities. Not sure if the kit will accommodate the change, but it's certainly worth looking at.
I was told to shoot for 1.5 oz fuel capacity, which should allow for starting, tweaking, walking to the handle, and 16 laps with a comfortable margin. I'll be using a Fox .15 BB that I picked up oh, 20 odd years ago, never ran it until Tuesday. It seems like a strong engine.
Is that the same engine in both your pictures? One shows side exhaust, the other rear, but the head looks the same. Does the cylinder mount in different configurations?

Gracious, Doc, it's 9:30 in the morning, surely your eyes are working better than that! 

Paul's model is with Nelson power, two different engines, one FIRE and FISE.

The models with (or to be for) the Fox was Jim Kraft's and/or Jim Mynes.

I forgot the dimensions on mine but it looks about the same as Pauls only a very slight wedge. Both the overflow and uniflow vents exit on the left side of the cowl. I am guessing it is just over a 1/2 ounce. I did find the smaller the tank the harder they are to fabricate. I have made several of them for my free flights I fly with a radio and old sparkers, so I am getting experienced.