Thanks to both RickNelson and Tabledancer for the responses!
The thread that comes with the kit does look a little hairy and I plan to convert this model for RC use, so that is why I didn't want to use the thread.
I find that "EZ Line" very interesting. I like the fact that it will flex and "give" like it shows on the weblink. That seems like a very desireable trait for use on an RC boat. Would help prevent something from breaking if the antenna wire were to hit anything.
Gave a little thought to making the rear two wires going to the stern the actual RC receiver antenna...but I'd probably have to use wire that is too thick for scale to make it work well as a receiver antenna. And if they were to break off, then my boat might end up disabled in the middle of a lake.
The EZ Line may be the ticket though (for scale looks), and just keep the functional antenna wire inside the WTC.