Yes, the stability problems made Grumman intruduce the taller fin (you are absolutely correct), which, BTW, was later taken over to the F8F-2.

I am looking forward to see yours with the HUGE propeller. I held the respective part from the Matchbox kit onto my conversion, and it looks intimidating! The most crazy thing: the Bearcat's tall landing gear makes its use actually feasible! But the I wondered about torque and low speed handling, and that made me switch to the five-bladed prop - and the "mixer" look, together with the fat spinner.

Some paint repairs have to be made, and the external ordnance is still on the work bench. But progress is good, I hope to be able to take (more) beauty pics towards the weekend.
I also made WiP pics from my conversion work and some details of the Art Model kit - all will be posted when everything is done.