Matt: The only thing you need to watch for is the length on the bolts. I think Al found that there are a couple of different lengths of 'em and in a dish, they tend to look the same. Have fun with it!
Bassman: I've got a 2nd un-cut cowl and plan to mount a 4 stroke totally inverted just purely for looks. After flying it with the 46, I'm rethinking my power choices. Originally I planned on using a Saito 72, OS FS-70-S2 or Magnum FS70 depending on balance. The 72 is the closest to the 46NT's weight. The OS and Magnum are 20 and 21 oz. respectively. I also have an unemployed OS FS-52-S2 which should be a perfect match for power but, it's a lot lighter than any of the others. A black plastic Master Airscrew 12-6 prop will help but...
There is no reason you can't use the original mount and angle for a 4 stroke as long as it will fit in there. The OS 70 and Magnum 70 won't fit but, the Saito 72 and the OS 52 will fit it. I downloaded the ARF instructions from Horizon's site and it said the distance from the firewall to the prop hub is 4-1/2". That's gonna be tight on the 70's....
The supplied landing gear is a really nice one! No worries...
Decisions, decisions...
Dave