Power adapter for Precision 670 SCSI drive?

I just received two new SCSI drives for my 670. I made sure I had the right cable, 68 vs 80, but the power connector is wrong.

The 670 has one 4 pin molex and two 15 pin. I need two more 4 pin molex.

FYI the 15 pin connectors have 5 wires.

What can I do to solve this.

I'm thinking something similar to the below, but it would need to be female instead of male.

Is this right or am I screwed?

All help is very much appreciated.

TIA Phil