Ya know, there's a fellow on here who does a little gunsmithin' work. He even "liked" your post, 18. Bet he'd take that trigger and make it do what you wanted.
And this is as good a place as any for me to thank him again for the work he did on my own 4566. Not as nice a one as yours, though it does have a forged hammer I like. BMCM went through the gun for me in addition to replacing the trigger play spring, and he stoned the trigger parts to smooth 'em up in DA. Made me decide to keep the gun after thinking I'd get it fixed and sell it. Not everyday you have a gun with a custom trigger job.