Fuel gauge Question?

[HOTROD]

On the after market Gauges what is the difference in 0 to 90 and 240 to33 and the last one 73 to 10 empty to full -if I was buying one (fuel level)!

[PA Dodger]

The numbers indicate the sending unit resistance at full and empty.  You need the 73-10 ohm gage to use with the factory sending unit.  The 0-90 is Chevy and the 240-33 is for the gage manufacturer's "one size fits all" sending unit.  I'm guessing you're looking at Autometer gages?

[HOTROD]

Thank You !