Rake, you should have a machine shop do it. Ream in a lathe or milling machine tell them you need an accurate bore, should be minimal or no cost. I am a tool maker and machinist by trade. If you talk to one of these guys there may be no cost.The hardware you have looks good. I use a tactic 2.4 GHZ two channel receiver, it requires no antenna. I push the receiver up in the left front sponson until it stops, then put a few drops of silicone on the edge. Eliminating the antenna should be worth some speed. I have over 50 runs on my bolt the only problem I have had was a steering servo.I am very pleased with the boat.
After watching videos on you tube I ordered a Piranha 400 if I had a bigger pond I would have gone with the 600.