Progressing - added two more images. A stabilizing bracket is needed to prevent flexing of the cold finger with the weight of the heat sink. Bracket will attach to tripod mount thread and the heat sink mounting plate. As mentioned, some wiring to complete.
The heat sink may seem like overkill. However, I selected it to have a significant margin over the sum of power dissipation requirements - that is, Peltier plus the power required to drive the module.
DeltaT is determined by hot side dissipation. I'll see how it performs.
Here