You really need to clean things up a little along with the springs.
I have drill bits the correct size for all drilled holes in a GP100 as well as the SP101. I hand turn them in the holes to remove any small burs, and slick them up.
You need to slick up some parts also. The Hammer Spring Strut is at the top of my list. Normally they are rough enough that I start with a File, then polish on the buffer.
https://gunner777.wordpress.com/2008/08/24/ruger-gp100sp101book-of-knowledge/
Read the above information on GP100 trigger Jobs about 3 times.
http://triggershims.com/ruger_double_action.html
This one is the source on Shims for the Hammer, Trigger, and Hammer Dog.
You can also get your Spring kit on the same order. He is a hair higher on the springs, but this is made up by shipping with the shims.
On the subject of which springs to buy. Who Makes the Springs, and who just resells springs they get from another source. My guess is Wolff is making Wilson and Brownells springs.
Back to Shims. The Trigger Shims, and Hammer Dog Shims are easy to install.
Not so for the Hammer Shims. You really need to make a Slave Pin to hold the shims in place, as you slide the hammer and shims into the frame. A dab of automotive
assembly lube also helps to keep the shims in place.
Bob