Complete kits are great, but in my experience, Willson triggers
are not the way to go. Even their high end "match" ones are
a problem. Go with a Videcki style, (HE hasn't made them for
some time,) but they are still being made. They are flawless.
Get a Brownell's 1911 catalog, and go from there. The best
matched parts were from Chip McCormick, but he can't sell
them anymore !!!!
Do it yourself, learn and enjoy.