Crutchfield has these JBLs on clearance and I was wondering if you guys think these are good replacement speakers using the stock EX stereo. In the future, I'd upgrade the subwoof, head unit, and amp, but until then, just a simple speaker/tweeter swap. Do you think these would be too hard to install on my own?

REAR-

JBL GTO635
$69
http://www.crutchfield.com/cgi-bin/S-zcTCdTuoIKE/ProdView.asp?s=0&c=10&g=52000&I=109GTO635&o=m&a=0&cc=01&avf=N
http://akamaipix.crutchfield.com/products/2001/109/l109GTO635.jpeg

FRONT-

JBL GTO605c
$129
http://www.crutchfield.com/cgi-bin/S-zcTCdTuoIKE/ProdView.asp?s=0&c=10&g=76400&I=109GTO605C&o=m&a=0&cc=01&avf=N
http://akamaipix.crutchfield.com/products/2001/109/l109GTO605C-1.jpeg