I am removing the above thermostat and replacing with honeywell RTHL2510C. What is correct wiring?

Letter Use Color (differs between manufacturers)
R heating power red
C common wire from secondary side of cooling system transformer or heat only system transformer changes
Rh power for heating changes
Rc power for cooling changes
Y cooling; cooling and heating on a heat pump; compressor relay yellow
W heat relay (W1, W2) white
G fan relay green
O cooling changeover orange
B heating changeover blue or orange
X common side of transformer, needed on some electronic thermostats blue, brown, or black
E emergency heat relay on a heat pump blue, pink, gray, or tan
T outdoor anticipator reset tan or gray
W2 second stage of heat pink or other
Y2 second compressor stage blue or pink
L indicator lamp blue, brown, tan, or gray
X2 second stage of electric heat black
F for systems that control fan in a call for heat none

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