Be aware the wood monogrips use another size screw, i have a wood set for my one GP100 and the screw size does not interchange. Also sometimes one needs to use a longer screw to seat the ruger monogrip then put the stud with the loop in. Maybe I will buy some longer ones and cut them down to avoid this. Its about a 2 mm extra thread you need.
As to lanyards, I do the KISS principle --- simple and cheap. I use the 1.5 MM accessory cord from REI or other sources. Mine are about 24 inches with a loop at each end --- I uses a figure of 8 follow though to make the loop. The 1.5 mm cord is small enough to go through whatever ring you have. I do that and then pass the lanyard though the loop to attach it without the need of any hardware etc. Then the other end I put through my belt. I then tuck the cord neatly up between my belt and pants / holster. Keeps it out of the way and allows it to play out if you draw. May not be expensive or fancy but it works.
I also frequently leave the lanyard out if I am storing my gun in my pack or sleeping roll. Gives a quick way to access the pistol.