LT1236A precision ref trimming

Hello, I'm confused with the datasheet for trimming the 10V "A" version of LT1236. In writing on page 7 it says I need a 75k resistor in series with a 20k pot, but the circuit diagram on page 8 instead uses a 50k pot. Is this diagram correct?Which trimpot value is recommended?

Also, when it says that by adding this trimpot, "Effect on the output TC will be only 1ppm/°C...". Is this drift in addition to the non-trimmed 2ppm/°C (typical) spec, or instead of? 

Thanks!