Quick, Easy question (Hopefully)

[Hugh Mongus]

I have been searching the forum and the web for this information, and I cannot find a definitive answer...

What temp sender can I use in vortec heads that is compatible with the factory temp gauge? I have seen talk about a machinist reducing the size of the factory sender, certain senders working at various temps but not all temps, and others trying different senders from Napa, but nothing that says "THIS ONE WORKS".

Can someone post a part number of a known working sender for vortec heads?

Thanks!!