Malpaso: The angles of the bearing surfaces of the sear and hammer must be polished correctly and equally, all the way across. A way to learn is to go through some gunsmith's or hobbyist's Wild Animal Box and find an old hammer and sear. (A lot of gun show tables have parts, but they often want money.
) Try to do it like the book sez; install, and try the feel. Take it apart and do it again, if needed. At some point it will be all worn out and you can do it all again. You'll eventually get it right.
We hope.
A way to get a reduction in the trigger pull is to cut a coil or two off the hammer spring. Don't do this until you have a replacement spring. You can wind up with a too-light hammer-fall, and the gun won't go Boom!
zot: Does the fit of the slide to the frame seem too tight? Are you having problems with the pistol not cycling completely? If not, I'm not sure you'll get any increase in reliability by loosening up the fit--unless you're planning on "Reliable When Full Of Crud". And a few thousand rounds through it will loosen it up, anyway.
Of course, you can always take some valve-grinding compound and work it back and forth until it's nice and loosey-goosey. Then, when you're not happy with 6" groups at 20 feet, you can send it to George and he can tighten it up for you.
Sorry George; couldn't resist.
Regards, Art