I am planning out the upgrades to my cherokee 140 160hp. I have installed an autopilot that has heading bug and tracking, it does not have alt. hold. So, here are the things I want; PMA8000BT audio panel, Knots 2 u main gear pants(I have eveything else they offer already installed), Dynon D1 portable AT backup(i fly ifr and hear it is a good back up), a new tach(mine is off 100rpm and I have replaced the cable), a JPI-700 or at least a JPI-450, and add the stec alt hold(system 30). How would you put those in order? Why?