So close to Powermac assembly- help with power button?

[Arctic]

After about a month, I now have everything in place but just need help getting the power button to work.

The attached image shows my issue: I have a slot on the logic board I believe is supposed to plug into the power button assembly (both circled). I have a little cable that is the right length and fits into the end on the logic board but don't see how exactly it is meant to connect to the power assembly.

Could someone help me out? Hopefully I don't need another power assembly?

In the mean time, can I bridge any of the contacts on the motherboard to entice this thing to start without the power button?

 

[DeltaMac]

If you look at the connector cable that you have now - you should have identical plugs on both ends.
You have a connector circled on the logic board. That connector is for the front panel board cable, so one end of the cable attaches there
There's a connector identical to that on the front panel board itself.
YOUR front panel board (where your top circle is located) appears to have that matching connector missing, or broken off - (or the front panel board is upside down, with the connector on the backside of what you have visible. I don't think that's possible, as the Firewire/USB/headphone ports would not be available through the front of the PowerMac case.) If the connector is missing or broken off, then you need a replacement power board. You can get those through internet sites that sell those old parts. The most common ones are newer, and won't work (they are completely different on the later PowerMac G5), so you have to be sure of the model.
The power button contact goes through the logic board connector pin 14, probably to ground. (pin 2 should be good for that) I don't know if the power will come on without the front panel board in place, as it may have other connections that are needed for power to come on. But, I don't have any way to test that theory. So, give it a try, and see what happens.