Delta shower valve body replacement
You may have the wrong trim kit. Many older Delta valves used 2 screws at the bottom (@4 & 8 o'clock) where the newer ones are located like your new trim kit @ 2 & 8 o'clock. Check to see if you can not find the right trim kit, but if the valve is old and you have access, it may not be a bad time to go ahead and replace it now and save the cost of the trim kit.
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