The hammer dog  mates with the trigger as the trigger is pulled back.
Use a paper clip to remove the hammer dog pivot pin . Remove the hammer dog, plunger  and the spring .
The hammer assembly...
Polish the hammer sear, but do not change the angles. Do not sand the hammer sear.
Polish the bottom side of the hammer dog and sand any rough edges. This is a factory fitted part. Be very careful not to remove too much metal or change the angles.
Insert a long, narrow screwdriver, bar, etc. through the hole in the rear of the frame grip and push the trigger guard latch . It may take quite a bit of force to press the latch. Be careful not to let the screwdriver slip off while pressing.
I prefer to hold the frame with my left hand while using my right hand to depress the trigger housing plunger. I press the muzzle into my leg during this procedure. I place a left hand finger in the trigger guard housing .
While pushing the trigger guard housing latch completely in, pull down on the trigger guard housing so the rear swings downward.
If the trigger guard housing refuses to move while the plunger is depressed, you may use a small screwdriver to gently pry the housing away from the frame. Do not pry on the seam where the trigger guard housing mates with the frame.
Remove the trigger guard housing.
Do not sand or polish the edges where the trigger guard housing mates with the frame.
Pull the trigger slightly and slide the transfer bar  sideways to free it. Note - Do not pull the trigger all the way back or the pawl spring  will launch out.
Sand any rough edges on the transfer bar.
Note - The pawl spring  will try to launch during this procedure.
Place the trigger guard housing in a plastic bag or hold your finger over the pawl spring. Carefully pull the trigger and slide the pawl  sideways to free it along with the pawl spring.
Polish the top, flat area of the pawl and the bottom area that rubs the frame. Sand any rough edges.
Place a finger in the trigger guard housing behind the trigger and use your thumb to push in the trigger guard latch .
While pushing in the trigger guard latch, use a paper clip to push out the latch retaining pin .