Unfortunately I can't be absolutely positive. All I've been able to do is to employ two researchers along with my own research, which includes copies of the registers in Salt Lake City LDS library and make an educated guess. The naming patterns of my 2x great grandfather (David Ambler's) children have provided clues as well.
Also I've never been certain that the David Ambler who was christened at Queenshead Bapteist Church is my David Ambler. The approximate birth time is correct according to the ages given in the 1851, 1861 & 1871 census, though. Do you have more info, Ian?