The -3 was the change that involved eliminating the recessed cylinder and the pinned barrel. Since yours is a 29-3, it wil not have a recessed cylinder, or a pinned barrel. Collectors call these P&R.
I have a 29-3 as well, and it is a fine revolver. Congratulations on getting it, and thanks for sharing it with us.
This is the only photo that I have of it right now...
Best Regards, Les