Henry A. Spellman wrote:
There is no difference in the measurements, although the later models
appear to be larger. The limiting factor is the main spar crossing the
cabin. The front of the spar is at the front of the second seats.

This is a fact. The cabin dimentions for all Comanches never changed,
other than to ad 5/6th seats to the later singles and twins.

Personally I think the back seat/seats are actually rather spacious
in Comanches. The hard part is actually climbing in and out.