foglight electrical question

95 xj
I'm doing a wiring upgrade for the foglights, heavy gauge wire, relay and so on. In the past when I have done this I've always used the existing positive lead that would normally go to the lamp as my signal wire for terminal 86 on the new relay. Can't do that this time because the circuit is screwed, when it isn't dead it's blowing fuses. I just want to isolate the old circuit and forget it.
So, the question is, what do I use as a signal for terminal 86 on the new relay?
Thanks,
Chris

The signal wire from the old factory relay. It may switch the ground side instead of the hot, use a test light to find out which and wire as needed.

Can't use any of the old circuit wires as they are dead and when I power up the relay it blow fuses so I need to run a new signal wire, but not sure from where.

What you are saying makes no sense. If you remove the foglamp relay does the fuse still pop? If not leave the relay out and use it's switched power or ground terminal to power your relay.

FIXED! The foglamp relays switched power was dead (never did find out why) when I jumpered power to it it would blow the fuse infront of the new relay.
The real problem was the stock foglamp switch, it tested ok when disconnected for continuity but did strange things when wired up. So installed an after market 3 terminal on/off switch and all is well. Good thing my labour is cheap.
MJR, thanks for the help.