1956 evinrude 15hp fastwin

ok guys iv had this motor for 2 weeks and after cleaning points and re setting them , re building the carb and making new plug wires it finaly purrrrrrrrssssss like a kittn!!!! last problum i have i cant figure out a solution too ..... the spark plug wires bind up in the mounting brackets and make the throttle stick so i can only get 75% throttle on it but if i pull the wire back it runs all the way up the slide , iv checked out pics and all others i can find the wires are routed the same way , dose anyone have sugestions befor i cut some of the mounting bracket off???

Do NOT cut the mount bracket. That would be a shadetree method of doing things!
First off there is about a full 2 feet of wire from where it exits the mag plate all the way to the plugs. If you don't have that amount then your wires are too short.
The routing, starting at the magplate is to run under the horizontal arm attached to the vertical throttle/magplate advance shaft on the port side of the engine. This is tha part that rotates and advances the mag. Then down to almost the bottom of the exhaust housing (there should be a spring down there that holds the wires) and back up again to the top port bolt of the cylinder head and through the bracket and to the plugs. This allows for plenty of movement of the magplate. Sounds like your wires are too short. New plug boots are easily available from dealers.
You didnt mention doing a water pump..........that should be done immediately to insure long term cooling. Can't replace those powerheads easily these days!
Always run that engine on a 24:1 mix.....nothing less! Do not pay attention to what Billy Bob or Bubba the mechanical whizz tells you otherwise. Anything less will accelerate the wear quickly in that engine. It is a plain bearing engine and must have that ratio to survive and give you a good service life. You may not send a rod through the block but you will notice your idle quality diminishing after several hours with the leaner ratios......usually a failure follows sometime after.
No, the plugs will not foul.
I routinely run opposed cylinder engines on a 16:1 ratio (using 50W aircraft ashless dispersant oil) with no issues and some of the very early engines run on as much as an 8:1 ratio and that is with less spark energy then you have in your engine.