I have just found a crack in my 20 year old Fowler toilet tank. Purchased an Estilo replacement tank but the existing mounting bolts don't line up with the new tank holes. Will have to drill 3 new holes through tiles and wet-area sheeting to fit wall plugs for Estilo mounting bracket but suspect I will not be drilling into timber. Worried that bracket might not support tank. Would appreciate any thoughts?? Thankyou. Peter