The DLE-20RA showed up today, so I finally unpacked the Hawk fuse and cowl to see how it would fit.
As you can see, in the cowl this almost looks like a joke. You'd think from this picture that this was a .60 glow engine, if it weren't for the plug. The picture doesn't even do it justice - there's gobs of room for an engine of this size in the upright position. There's at least 3/4" above the plug, and all kinds of space in front of the head. There's enough space above that I am thinking of opening the upper intake and turning it into a cool air duct for the carb, if I can figure a way to route it around the exhaust.
I set up the fuse and test fit the engine with the Hangar 9 Ultra Motor Mount set I intend to use rather than the stock one (to allow more clear space around the carb), and I will need 1/4" standoffs to get it to reach the front of the cowl. In other words, it fits perfectly. For the heck of it, I pulled out an Enya 1.20 4-stroke I have, and fit it on the same mount, and it appears with some creative exhaust routing it too would fit in the upright position. Clearly many engines would fit in this position. And I won't have to cut any part of the cowl, other than the slots to install the Keleo exhaust (and to open the upper duct intake).
Early in this thread a few guys asked about upright motor mounting, and were immediately told it wouldn't fit without cutting the cowl to bits, and that cooling would be impossible. Well, the first is demonstrably false, and the second I intend to disprove over the next few weeks.