sorry Buttsahib Bhai, i am not into These Speakerz and Stuff or i would have Loved to Guide u.
i dun think Cars should have this MUCH of Sound Effects. i mean 4 Speakers are Enough, and Woofer !! i dun know What Does That Thing DO !! .... instead u should save ON and do repairs/maintainence on your RiDE (if Needed, warnaa aur bhii kaam hotae hain dunyaa mein yara).
i am Not a Mehranist or a Guy who knows Mehran Well BuT i might be a keen Observer, and if i am NoT wrong then :-
For Crystals:
Dont go For Front Crystal in your Mehran, as i Have seen Many on Roads AND they just Look hidious.. i think New Mehran has Some minor Body tweaks to iT which helps it to accept the FronT Crystals, old mehrans with Crystals LooK SLUGGISH... For Rear STOCK is BEST (again)..
No Offense intended Bhai.
Regards.