Let's hope someone with HD8 experience sees this thread and joins in, Rong. From Rodeobob's comments it seems the HD8s he has seen have varied in a number of details. My guess at this stage is that your mower did not originally have that Briggs, because it is so much older than the mower seems to be. Whether there is any way to tell whether its original engine was a Honda or a Fuji is a mystery. Also, Bob seemed to be saying that he has seen two different models of Honda engines used on them.