RE: Kangaroo: 4 or 2 Elevons?
In mine I joint the elevon halves and still used tow JR8611 conected to a matchbox. Of course way overkill, but I did it because the guy who build the plane for me did not sand any glue area. So I dismantle the jet and almost rebuild it again.
Elevons were allraedy glued so I decide to use two servos just in case the glue joints failed.