Good morning. I recently replaced a failed heat pump in a room over my garage. I had the installed leave the old thermostat so I could replace it with a Nest Thermostat E that I purchased later. Needless to say, things were not as simple as they seemed. I've installed a few Nests before ("installed", aka followed the instructions) but this one is a bit different and was hoping for some wisdom.

I'll attach photos but here's what I've got.
Honeywell terminals are: X, W2, B (across the top) and below that R, G, O, Y, E, and W3.
Wires coming from the system to the Honeywell
Blue - not used
Black - not used
Brown --> X
White --> W2
Orange --> B
Red --> R
Green --> G
Yellow --> Y
Unused terminals on the Honeywell: O, E, and W3.

The Nest Thermostat E has only six connections: Y1, G, R, W1, C, *OB. Any ideas? Thanks.
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