[Pathfinder]

Just been doing some research into the Ki-61.

As far as I can see there are three variants but I'm sure there may be more. These are the ones I have:

Ki-61-I-Hie
Ki-61-I-Tei
Ki-61-I-KAIc

Anyone know of any more?

I can only find one external difference and that is on the K-61-I-KAIc which appears to have six exhausts when viewed in profile, instead of the normal five. I assume there is a different engine type or modified engine which would explain the extra exhaust?

Are there any other external differences?

Thanks
Pathfinder