If you are getting 219whp all motor, then you probably need to go in the opposite direction for a turbo. I imagine that you have high compression pistons, so you may need to lower that to something like 9:1 or 9.5:1 to run a reasonable amount of boost.
I imagine that you also have some pretty aggressive cams. You may need to go back to stock or get some aftermarket cams that are designed for turbos. I don't have any first hand experience with this, but from what I've read, if you have very aggressive cams with high overlap and then run a turbo, you end up blowing the boost right out of the exhaust ports...
Also, if you are trying to run high levels of boost (like 10+psi), then you should look into resleeving your engine.
As for maintenance, it all depends on your dealer. Some may know how to deal with a turbo and some may not. You only need to get the oil changed every 2000-3000 miles with a turbo, so you should be fine with your 1500mi oil change routine.
If you are serious about boost, then don''t bother with a greddy kit. Take a look at the rev-hard kits...
www.revhard.com