Under bed Fuel cell questions
 

I've searched and searched and just can't figure this out.
Doing a fuel cell under the bed with external pumps and just need to figure out the sending unit crap.
I have an 01 so its the 40 ohm empty and 250 ohm full unit. Correct?
I can't seem to find that sending unit anywhere. I can find the opposite
250ohm empty and 40 ohm full.
Is there a way to make that work? If not, what is everyone doing to make this work?
Thanks.

You can change the tune to run a different sending unit. I have done it before

Really? That's some good news.
Is that somewhere in the Fuel Tab in HPTuners?
So I would be able to use just a universal 40-250 ohm sending unit?
Any idea how to wire it up to the existing wiring harness? Which wires are for the Gauge?

I've seen someone post a wiring diagram for a nnbs truck on here a while ago. Is there anyone that has one or can get a fuel pump harness wiring diagram for an 01 GMC?

dbrods makes a really nice fuel cell that has the stock pump basket in it. Lets u use the stock pump assemblie to keep your fuel level. He adds a sumped bottom with fittings for external pumps if needed.