ok...do you have the locations of all those pics?...meaning where each one is located in the bay?...pic one appears to be too small for an inline fuel pump, at least the ones I have seen...My old probe GT had a filter that looked identical to the second pic, with a line in on the top and out on the bottom...but I never got around to changing it...and I don't know what pic 3 is either...but they all appear to have fuel lines running into them, so theoretically they could all be different types of filters with different elements for screening different things...
Now I try to do everything I can to my own car...and if there was one thing I would never even consider, its cracking open a gas tank...fuel lines are scary enough...But the amount of vapor realesed when you crack a tank is nuts, and a bad electrical outlet could turn your garage into a mushroom cloud if the conditions are right...not to mention how hard it is to seal up again...Gasoline, having very low viscosity, is hard enough to keep sealed into anything...and once you pressurize the system again, it will test the work of anyone...keep that s*** away from me...