Striper, I am not sure what you did, but it sounds like this. You pushed the safety too far over and the spring and "plunger" that holds the safety in place came out. Is that where we are at? Usually in disassembling a Model 12 for blueing, a paper clip is required to pushdown on the plunger through the hole in the safety put there for that purpose. Then you rotate the safety 90 degrees with the clip and the safety can be pu8shed to the side and removed. That hole is on the left side of the trigger-guard
Put the spring in the hole that will be under the safety. Put the plunger in the spring. Make sure the safety is rotated 90 degrees to that hole and push it on through from the right side. When it is flush with the trigger guard on the right side, rotate the safety so the hole in the safety is in line with the hole the safety plunger is in.
If you can't understand that, take it to a gunsmith that reblues Model 12s and he will do it right.