There are separate form ID values for an object definition and a placed instance of that object.
You can view the form ID of the placed instance in game by opening the console (press the back-tick) then clicking something.
The first 2 digits (source mod index) is the number of the mod load order.
Objects from the base module (first loaded) will be 00
.
The second-loaded mod will use 01
.
Objects belonging to a save gave will use FF
.
Instances can be quite common, like from generated items.
module.exports = (state)->
new Promise (resolve, reject)->
if state.buffer.length < 8
reject 'Missing data for form ID.'
else
#source_mod = state.buffer.slice 0, 2
#object_index = state.buffer.slice 2, 8
resolve state.buffer.readUInt32LE 0, 8