About this detail of the Tiger
The Tiger B had a HL 230 engine similar to the Tiger E, but the arrangement of the cooling air flow was different.
The exhaust shrouds on this vehicle apparently did not lead to a duct. They were extended to the hull rear wall, or close to it, as drawn above. The main exit point for air was the vent halfway along, as shown in this diagram of the right-hand shroud [2] .
The same exhaust shrouds could be used on Tiger E and Tiger B because the vent could be sealed and the extension was a separate part. This is an extension from the collection at Bovington Museum [1] .
The extension had 4 bolt holes in a flange at the forward end. It could be used on either the right or left exhaust pipe, because only 2 bolts were needed.
[1] Survey of Tiger 250122, at Bovington museum, by David Byrden
[2] Workshop drawing 021 B 425 B1 : HL 230 external dimensions