4-20mA to 6-144 inches using AM2

I am trying to scale an analog sensor that is set up for an output of 6inches to 144 inches. on a 4-20mA signal. 

The closest thing I can get is my gain set at .14 and my offset set at 6 but that makes my min 6 and my max 146. 

I have a analog amplifier in front to scale from 0 to 1000 then the next scales from the numbers above. but I cant get it to the desired numbers.

Closed cause question posted twice.

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