In all honesty I realized this issue months ago, but didn't want to be the first person to go on about the southbend disk. Everyone else had superb reviews on it so I just kept my mouth shut, till a few threads about the same issue showed up. I realized that some reviews on products are not always the real story.

Anyhow, new fork, ball, 1mm shim, slave and ACT disk is what I'd do too.

My ACT streetlite flywheel is at 0.618", It can go deeper if needed.

Also FYI the ACT 6 puck sprung is a few thousands thinner than an ACT street disk. Its a little harsher but not as bad as an unsprung 6 puck. If quick release, good pedal height is what you are looking for, thinner disks are the way to go.