You can mod both to get the gear you want. Not hard to do. I've seen more Tigers modded to tail dragger than 4* modded to trike gear.
Basically you just get some aluminum gear and mount them so the axels are under the leading edge of the wing. Pick up a tailwheel and mount that on the back and you are good to go. There should be some good posts around here that go into more details.

I would also like to correct myself. The Saito 82 would be a good engine, but you might be more pleased with a 90 or 91 4stroke. if you wish for unlimited vertical even a 100 would be ok.
When I get my new one (been saying that for 6 years since I dorked the old one) I'm going with a 91 I think.

Ahh the memories.