Gary Lewis wrote
I'm not 100% sure I understand your question, but black is almost always ground, and Circuit 57 is ground. But the "727 connector" bit throws me.
It looks to me like 727 is just a normal 2-pin connector passing the two wires. So I thought maybe you meant "717", but its pin-out shows a connection for #57 and another for #57A, and I assume the latter is from the VSS. So I'm guessing that the speed control amp itself passes a ground signal back to the VSS to complete the circuit.
In any event, I believe you are safe grounding one side of the VSS and sending the other to your aftermarket cruise system.
I think I worded my question wrong, but thanks for confirming what I was already fairly certain of;). I'll just ground one side of the VSS. Easy as pie. Thanks Gary.
1994 F150 4x2 Flareside. 5.0 w/MAF, 4R70W, stock.
1984 F150 4X2 Flareside. Mild 302 w/ 5spd. Sold.
1980 F150 4X4 Flareside. 300i6 w/ 5spd. Sold in 2021.
1980 F100 4X2 Flareside. 351w/2bbl w/NP435. Sold in 1995