Nice! Quick work too.
I am sure you are very familiar with Cox engines, but I thought I would mention a few things anyway.
The Pee Wee is a good engine, but....they are super finicky! Everything relating to the fuel tank must be air tight. To include: Venturi o-ring, backplate, backplate screws, crankcase to tank gasket, tank to backplate seal and NV . If anyone one of these is allowed to draw air it will run like garbage. It generally takes me a couple hours to set a pee wee up properly before use. Even out of the box they fail the tank pressure test.
Anyway, just thought I would mention it as evenly matched steady runs are a good thing on a twin setup, plus it looks like they are cowled in pretty well and might be a pain to remove.
Have fun with it!
Ron