Refer to the following guide on removing the retainer ring and replacing the diverter for the Forte K-10430 or K-10434 Kitchen Faucet.
Use a 5/32" hex wrench to remove the set screw from the back of the spout. Pull the spout up to remove it from the body.
On the underside of the spout that is removed, locate the silver colored retainer clip.
Pull the retainer clip out using snap ring pliers or needle nose pliers.
Remove the diverter using a needle nose pliers.
Install the new diverter and reassemble the faucet.