In my old 2013 FG MK2 XR6 ute i had two Alpine Type S 12" subs(not slimlines), Got some big Aeropro boxes from supercheap or autobarn for around $50 each. Then just wired a line out convertor off the rear speakers. The full size subs did take up a little bit of room, but im just on 200cm and could still fit in pretty comfortably.
If you go onto "CLUB FG" on Facebook, just put a post up asking for ute sound systems setups and you'll find some people have really nice setups. probably wont find any posts if you search as they had to make a new page
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