JPL-- the engines or the superchargers? The engines are not very diffierent from the roadbike engines they were derived from. If you mean by "Kawasaki" the Kawasaki dealer, that is always your best bet if you can find a competent one. For one thing, they will use good quality parts, which many others won't. Otherwise, any engine guy who is thoroughly familiar with inline four Japanese engines will do a good job.