I AM REPLACING THE WATER PUMP IN MY 1999 FORCE 120. WHEN INSTALLING,I HAVE ABOUT 1/2 INCH GAP. THE LOWER UNIT WONT SEAL W/ THE REST OF THE ENGINE. SHOULD I JUST TIGHTEN THE BOLTS? IS THIS TOO MUCH SPACE? WHEN REMOVING I HAD TO BANG A LITTLE TO GET IT OFF. THERE IS NO REFERENCE IN THE BOOK. CAN YOU HELP? THANKS.