How to adjust pump settings

Hi I've recently cleaned out my system with x800 and refilled with an inhibitor, system is noticeably quieter.
Can anyone explain how I set the boiler and heating pump speed. According to the manual you do this during commissioning when the heating isn't on, but without the heating on I can't check the temperature at the pipes accurately. The pumps are all set to 3 at the moment but this seems over kill for 8 radiators and 2 towel radiators.
Also the flow temperatures across the radiators are the same 50c at Inlet and outlet, I can't get a 12c drop even at a quarter turn. Could this be the pump setting?

Thanks.

This is what it says in the instructions.

• If the boiler is range rated, then adjust it to the maximum heat input.
• Check the boiler thermostat is set to maximum.
• Set the boiler pump speed so that the temperature difference across the
boiler is about 8°C - when the space heating is off. NOTE: For optimum
performance when using a condensing boiler such as the Keston C25 set
the boiler pump in the BoilerMate to give about 15ºC temperature rise across
the boiler.
• Set the heating system pump speed so that the temperature difference across
the heating flow and return is not greater than 11°C.
• Check the DHW plate heat exchanger pump is set