Just this past week I successfully used NG7M's video to integrate MMTTY FSK to my K3S / ACOM 2000A station. I strongly recommend it. I really like dropping the received tones down to 915 Hz from the default setting. I did have to use a multiple of 4 for my sound card sample rate, another excellent tip in the video.
Integrating to N1MM+ was a snitch.
I attribute my success to the NG7M YouTube video. It is found very quickly by searching keywords NG7M FSK on YouTube. 2 thumbs up.
Also, I did purchase a N6TV designed Y BOX too. I strongly endorse the use of that accessory port splitter box. It avoids the mess of multiple splitter cables. It makes it easy to access the FSK port yet does not interfere with other devices the require accessory port access (i.e. P3, SteppIR, or other devices needing band data). Bob N6TV gives outstanding tech support.
I really like the AA5AU diode OR'ing trick for doing SO2V operation too. A really simple way of paralleling 2 serial comm ports for PTT & FSK functions.
Bottom line, I would buy NG5M, N6TV, & AA5AU a cup of water at Vasalia... (watch the video and you will know what I'm talking about.)