Yes, new ambient sensor was installed. I wondered what the difference was but did it according to the directions.
Steps I followed were:
1. Remove existing wires/connectors from original 12 button board and remove board.
2. Remove existing ambient sensor and install supplied sensor from kit
3. Cut slit in harness to relieve strain
4. Cap off yellow wire from fan
5. Plugged in both RJ-11 connectors, new red ambient sensor, white remote senor cable, blue freeze control, 6 pin connector to new 5 button board.
6. Set dip switch for furnace (all others off as this is a zone 1 unit)
7. Mount new board, and then black fan motor wire to T1, Red fan motor wire to T3, Violet RV wire to T4, 120V input black wire to left K6 terminal, blue compressor wire to right K6 terminal
8. Spliced second violet RV wire to white wire (which terminated at run capacitor with other white wires).
9. Connected 120 volt lines underneath, connected both furnace leads, connected both RJ-11 connectors, left the two yellow wires alone as nothing on MH to attach to.
10. Reset CCC to get FF code and gave test. AC, heat pump and furnace all ran fine.
11. Went to put cover on top but noticed RV solenoid was somewhat hot to touch (after a period of rest) and discovered it was energized with CCC in OFF position. The only time it seems to be not energized is when running in COOL mode.
Photos of my work available at: smtlm.org/heatpump.html