I’m almost done swapping my 98 corvette form an ls1 to an ls2. I’ve ordered harness extensions 3 times none of which fit correctly. 1 of which I can modify to make it work though.

is it just extending the wires or is any of the wires switching pin location?

 

If you're not using the little pigtail on the front cover then just extend the 3 wires and swap the 2 outer at the connector. If you're using the pigtail then its wired straight.

 

so the pig tail swaps it, sounds like an engineering flaw

 

Might easily be a different sensor design that happens to use a different wiring arrangement. Keep in mind you are adapting one OEM setup to another.