That's not the inner fender - it's the shock/spring tower. The inner fender is the plastic wheelwell.
I don't think I've ever seen a good diagram showing how that hose is attached to the tower, but I'll try to essplane...
1) Remove the hard line from the inboard side of the tower & pull it clear of the fitting on the tower. Cap the line to prevent fluid drainage.
2) Find the 180° bent end of the spring clip, and lift the OTHER end away from the tower (over the fitting), then push the clip sideways off the fitting. Any pick tool should work.
3) Pull the fitting end of the hose out of the tower.
Yes, it's possible you have phenolic pistons, but there's nothing wrong with them. They transfer LESS heat to the brake fluid, and they're more dimensionally stable than metal (they don't expand/contract). You can probably find reman calipers with whichever type of piston you want, and they should be ~$25 ea either way.
The biggest problem with these brakes is overtightening the lug nuts.
Stay OUT of the zone!

Take that $#!+ back & buy from Advance or O'Reilly. JMO
