i have a set of blaupunkt gtx 663's laying around

their technically 6.63 inches (oversized 6.5's)

i checked on crutchfield and both the door and kick panel have 6.5's
the depth is 2.2 inches i know..

the thing is they are meant to be powered by an amp, 50 watts rms with a peak of 220

just wondering where i should put it for best sound quality, and do i need an amp? i can't just buy some adapters and stick it in?