First off I would recommend you purchase a second spring vise or one of these for the frizzen.
If you want one you can get them from Dixie.
My process is a bit different.
Move the hammer to full cock.
Close the frizzen.
Attach a spring vise to the frizzen spring and tighten just enough to take the pressure off the frizzen.
Remove the frizzen spring screw and frizzen spring and set aside (do not remove the vise).
Remove the frizzen screw and frizzen as set aside.
Attach a spring vise to the main spring tight enough so it does not fall off and slowly release the hammer (this will release the pressure on the spring so it can be removed).
(For locks with a link between the mainspring and tumbler this is when it is removed.)
Loosen the hammer screw (do not remove until latter).
Remove the sear spring screw and remove the sear spring.
Remove the rear bridle screw and sear.
Remove the front bridle screw and bridle.
(I'm not sure if your lock has a fly, if it does be careful not to loose it at this point.)
Remove the hammer screw.
Remove the hammer (this may require the use of hammer puller [a small gear puller will also work]
Remove the tumbler
Assembly is in reverse order.
NOTE: Installing the sear spring requires loosely installing the sear and spring and then pressing them together until the spring slips into its index notch and then tightening the spring screw without releasing it.