If you mean molex for power most of those connectors can be rewired as in you can remove the pins and put them in the correct order if not you can always cut the wires and resplice them in the correct order.
If it the data portion I'm sorry I can't help you with that.
Also what can you actually do with a thin client? I thought they were like "dumb" terminals from many many many years ago and thus do not work without some network server on the other "end" as from what I know they don't have a local OS.
Modern day thin clients are pretty much under-powered PCs at the moment. Plenty of them running around with DDR3 era tech with low CPU and GPU specs. For example i bought a lump of Wyse (Now dell) ZX0 with a 1.6ghz AMD cpu 2 cores, 2 threads at 1.65ghz with a built in Radeon HD 6000 GPU. Some have no ssd and most didn't have the power supply for just 12 bucks each.