Which 6.5 Components

I am considering installing Polks in my Volvo V50. Actually I have some Polk Mobile Monitor 6501 from 1990 in the car now and they really sound good until pushed. Then they show their age as they have been through a lot. They look just like the old MW65xx used in the vintage Polk home speakers.

The V50 has the Premium Sound with Dolby ProLogicII which I don't use. I am mainly using just the front door speakers, which are 3-way (6.75" woofer, 3.5" midrange, 1" textile dome tweeters on the pillars. The XO's are 2nd order high-pass. The system has an external amp by Alpine that is rated 70W RMS but not sure at what impedance. The factory speakers are marked 4 ohm but their static resistance measures 3 ohms. I know usually manufacturers like to inflate the numbers but this thing really cranks, is very fast and is clean.

The system would likely drive the MM6501's but I am also looking at the DB6501 and the DB+ (DB6502). There is plenty of room behind the speaker so depth is no issue.

I welcome any opinion on which would give the best SQ. I am good with going 2-way.

Thanks
Stan
Stan

Main 2ch:
Polk LSi15 (DB840 upgrade), Parasound: P/LD-1100, HCA-1000A; Denon: DVD-2910, DRM-800A; Benchmark DAC1, Monster HTS3600-MKII, Grado SR-225i; Technics SL-J2, Parasound PPH-100.

HT:
Marantz SR7010, Polk: RTA11TL (RDO198-1, XO and Damping Upgrades), S4, CS250, PSW110 , Marantz UD5005, Pioneer PL-530, Panasonic TC-P42S60

Other stuff:
Denon: DRA-835R, AVR-888, DCD-660, DRM-700A, DRR-780; Polk: S8, Monitor 5A, 5B, TSi100, RM7, PSW10 (DXi104 upgrade); Pioneer: CT-6R; Onkyo CP-1046F; Ortofon OM5E, Marantz: PM5004, CD5004, CDR-615; Parasound C/PT-600, HCA-800ii, Sony CDP-650ESD, Technics SA 5070, B&W DM601