I Just put my kappa perfect 6X9 two ways in my rear and moved up my 6.5's to front, and what a suprise to it was!
I had my custom housing materials ready to go to remove what I thought were 4X6 componet, but when I opened the bottom part of the panel I noticed something, the previous owner had put in a custom housing for 6.5" heh
so I just had to drill new holes for the newer speakers to put in, and put everything back together and now I get more noise! heh
so I had to do jack shit for custom work
everything in total took about 3 hours, since I had pretty much all of the work done.