"2) is that something I could do without need of a gunsmith?"

I found it to be a pretty easy install, but have also
worked on triggers prior to installing in a 700ml and a
788. Knock out a couple of pins with a drift punch, pull
the existing trigger, replace and punch the pins back in.
The adjusting screw and lock nut on the front of the
trigger required using a dremel tool on the stock for
relief, but the rest was a piece of cake.