I have installed a Timney trigger on my LH Ruger Mk II Sporter.
It was easy, sort of. You will have to file the trigger to have a good fit on the safety cam.
Go real slow and file it squarely.
I used the stock spring with the Timney trigger and sear to give me a very crisp 3.8 lb pull with not over travel.
If you use the Timney spring, the pull is about 2.5 to 3.0 lbs, which I found way to light for hunting.
Timney makes a great trigger, but be ready for "just touching" that trigger. My first few shots were all over the place due to me not getting the feel for the very light trigger trigger. The stock M77 Mk II tigger was about 7 lbs.
Also, always test the safety engagement each time you "file and fit" the new trigger.
Also, you will have inlet the stock just a bit. I used a round sanding bit on my Dremel to remove about a half round shaped area about 1/8" deep.
I think the new Hawkeye Mk IIs have better triggers and you may not want to put a Timney trigger in.
Also, the LH trigger is different from the RH trigger due to the safety being on the LH side vs RH side.
I have stainless sporter M77 Mk II and it is my best deer rifle.