Reconnect Speedo cable and multi plug connectors !!
Push Back into position !! Screw in original screws in each corner !!
Put Visor back in place !! Job done !!
What might be happening is the speedo cable when you have been trying to get it out pulled it through a bit from the bulk head and now your trying to push it back in its the cable stoping the dials from going back !!
Try to push the speedo cable through into the engine bay a bit then recconect the speedo cable !!
HTH
LEE