First, what model-year SHO - and if it's 93-95, ATX or MTX?
Can you tell where the leak is?
Have you pressure-tested the cooling system?
Why are you getting the rid of the hard-wired fan? More importantly, what are you replacing the fan with?
The best way to "research" a harness issue such as this, is the get the color-codes for the wiring harness from the EVTM (Electrical and Vacuum Troubleshooting Manual), and see if the wires in the clipped wire harness match. Realize that you can have more than one wire using that color-code, but I don't recall ever seen this in the latter-portions of a wiring harness (ie. a harness-lead).
For example, the 1994 MTX has four wire feeds from the CCRM to the Electric Cooling Fan, that drive the 3-phase motor. Two feeds off the CCRM (Constant Control Relay Module) are BR/O (Brown/Orange stripe) that are joined at harness splice S134 into a single BR/O wire prior to the harness connector C190. The second two feeds from the CCRM are DB (Dark Blue), join at splice S135 into a single DB wire at connector C190. At harness connector C190, there are three wires in the harness that then leads to the fan - wire 181 (BR/O), wire 228 (DB), and ground wire 57 (BK). The base part number for connector C190 is 8K621, which is a black 3-wire connector.
The 1994 ATX SHO (dual fan) is completely different for the most part.