Will take a stab at the last question, the Lightning bow is unlikely to fit the Tavor 7 unless you are ready to consider re-machining the bow (Am not sure with weight reduction machining done by Geissele if you'd be able to get the set screw re-installed if you did).
It will fit the original 21 and x95 models fine.
Main issue on the 7 that I had the luxury of getting to mess around with, and something that I believe others that have tried have also encountered, is that the new style of safety mechanism interferes with the backside of the Lightning Bow where the set screw meant to take up slack in the linkage is located.
One thing will also note is that the bow in the 7 is now a single piece and drop safety likely just achieved through the now differently positioned spring. Some of the original Tavor model deficiencies on the front of the linkage may not be as pronounced. Have some pics from back then that might do a better job in highlighting the difference, linked them here temporarily to help. Apologize in advance for doing that in a business thread if that is not the appropriate thing to do. Can move them to the TAVOR FAQ if requested.
Default Tavor 7:
Poor attempt of overlaying a Lightning Bow, much more of a PITA to unhook the linkage than it is with some of the older Tavor models. Don't have a pic of the bow sitting in the slot as I didn't remember to take one and wasn't going to try disassembling a second time to take it.