There come times in circuit bending when I just don't feel like putzing around and finding the clock's source for proper syncing. Sometimes, I feel like it just doesn't exist outside the silicone of those random NEC chips.
Let's take my Casio MT400V which mysteriously sat unopened for 5+ years ($1 garage sale find). Popped it open Sunday, and spent the better part of the day tracing around and trying to find the sync signal.
I've done this in the past and it always worked and I should just do it from here on out: LED. Thats right, tie into the LED that is showing you the tempo! Toss in a simple transistor circuit there and bam! Clocked gate for your Eurorack. I used the PEG to multiply it up and the MT-400V was synced up with my modules.
Let me know if you have any questions.
Also, check out PartSim. It is a super easy to use online SPICE simulator. Should help you dial in your transistor circuit for the gate.
PartSim - Online Circuit Simulator with SPICE | PartSim