Pat, sounds like you've got some good engines to set up a 46 Do. I've seen several guys with U Can Do's that were set up with too small of engines and they don't have enough power to have fun with them.
As far as tips with the 46...... Make sure you pin the landing gear block. They are notorious for coming out and because of the design of the fuse it's hard to get any more glue in there. What I have done is to turn the fuse upside down and drill a couple of holes at an angle and put some pins in the holes. What you want to do is to drill and pin it so that you are pinning the block that the gear attaches to, to the plywood wall that's there. Otherwise the block will pop out fairly easily on even a decent landing.
Also, don't use the wheel pants until you're certain the landing gear isn't going to pop off otherwise the wheel pants will poke through the wings. You can even replace the landing gear bolts/screws with 1/4-20 nylon bolts. That way if the gear does break off it won't rip the bottom of the fuse out.
Also the tail CA hinges seems to break from vibration so it's a good idea to use pinned hinges or something other than CA back there.
I can't remember what else to do with them at this point, I'll have to think about it and get back with you.
I've had 3 or 4 of the 46 Do's and 1 - 60 Do and 2 Hangar 9 Frenzy's. I didn't care for the 60 Do all that much. I like the 46 Do and the Frenzy the best.