im not a pro but i think if you fit a turn fin on both sides thats gonna cause probs? theyre hooked or shaped to hold the boat into the water for turning in one direction- at least mine is(just a visual copy of the micro renegade)
when you turn it keeps it anchored into the water and thats why when you turn the other way it actually lifts it out of the water
regards the rudder side-on the renegade its fitted on the left! (from the rear) but i have no idea if that makes any difference to the handling sorry!
good luck with your build

Graham