Fuel sender ohm question

[sandking]

I did search and confirmed that my '72 Blazer does need the 90 ohm sender. I had recently bought a 26 gal fuel cell (used) that has the 240 ohm sender. I know the gauge will not work with this as it would probably read half tank when its empty, right?? What are my options? Is there any way to "fix" the resistance of the sender? Or would it be better to just buy a new sender? I have never replaced a sender, is it just a matter of cutting the rod to length, and thats it? Thanks for any input.