GPU in a Dell VRTX

I was gifted a decommissioned Dell VRTX with 2xm640 and 2xm520 to move my homelab to. Trying to determine the pinout of the 3 6-pin gpu power cables in the GPU chassis to see how I could convert to double 8-Pin for my 2080 Super I have sitting around. Want to run Stable Diffusion on it and other GPU accelerated tasks.

Anyone familiar with this Chassis and if there is a way to power this 2080Super? I think I can get it to fit.