My delta shower faucet is leaking, how do I install the seat and spring correctly ?

I have tried to find a good explanation of repairing a DELTA shower faucet

Most good hardware stores have repair kits for these faucets

Believe they give a detailed drawing and tell you how to repair them

Delta Faucet - Faucet Repair, Maintenance and Installation Information for your Delta Faucets

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This should help. Biggsie put it up and all I did was expand on it a little. You should be able to shut off the water and using the diagram locate the seats and springs. The part number is 4 and any Delta dealer carries them. While you have the valve open turn the waqter back on for a minute to flush out the supplies and valve bosy. Good luck, Tom