Those speakers will electrically work okay (they may not be quite as loud as factory) but I have no idea how they will sound to your ears. I believe the factory door amp has a low pass filter built in to it so there probably won't be any high frequencies coming out of the door speakers, coax or not.
Just an FYI, the factory door speakers are 2 ohm units which are not common. I don't think anyone has found an aftermarket speaker that is identical to the factory units in dimension and impedance. So if you are going to keep the factory door amp, using a 4 ohm replacement speaker that physically fits is about the best you can do. Also, here is a little more info about how the door speakers are wired:
https://www.ft86club.com/forums/show...7&postcount=35