Thats cool. CVs shake when you're ON the gas, in my experience. Tie rod ends are first to go up front, and those def cause highway shake too. Cheap n easy to replace, also. Then of course tires on a $500 ride are gonna be who knows. If you can tuna fish you'll do fine with the GP, SEs look catfish-esque up front, kinda. I like 'em. Enjoy your project, these things are great bang for the buck rides.