Help - dash wiring issue

[RLTW06]

I am re-wiring my dash (63 Series IIa) and when I reattached the battery, the speedo cable started to melt where it was touching the dash. The entire cable was hot to the touch. Trying to understand where the short could be. Any thoughts. Could someone share a pic of their dash wired up? Thanks.

[SafeAirOne]

The schematic is essentially a pic of the dash wired up.

Is the instrument panel grounded? Right now, it sounds as if the speedometer cable is your ground.

[Tim Smith]

Agreed but I think rather the speedo is acting as your ground for the engine. Add a ground from the engine block to the chassis/battery to fix.

[cedryck]

Agreed Tim, ground the engine to frame, some ground battery box as well. I grounded the Starter motor bolt, as well and in my truck this made a huge difference on how it started, first time hitting the button.