the trim goes overhead on left side..
usually the throttle is removed when left door is added....
I just finished adding throttle in left cargo door on this -12 & its removable assembly also, but need to finish making sure I get it all approved before I really share and someone thinks its a easy done deal....took some thinking... but now have methods figured out for the -12, and if you do a left -18 door to keep it in original location also(different methods for each)
you might contact crosswinds since he holds one stc for it (think larger cargo door version it's -14 only, you will need a fsdo field approval for -12
http://www.crosswindsstol.com/ prolly can give you a good idea of whats involved $ wise
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