Start by disconnecting the power to the fuel pump switch on your Ford. You will then disconnect all electrical connections as well as vacuum lines attached to the manifold. Take out all electrical connectors attached to the injectors then also disconnect the fuel rails. Rock them gently until they're fully detached. To clean the injectors, run the pressurized solvent through them.
I had a clogged injector on cylinder 2 on mustang, verified spark at coil and plug but injector wasn't firing. A friend told me to take a long screwdriver or something similar and butt it against the injector where it goes into cylinder and gently tap screwdriver with mallet, it would help loosen up whatever may be clogging it. Damn it actually worked..saves myself $90