*I'm not copy/pasting the entire wiki page for the Panther...
... But I will copy the Panther Ausf. F part:
After the Panther II project died, a more limited upgrade of the Panther was planned, centered around a re-designed turret. The Ausf F variant was intended for production in April 1945, but the end of war ended these plans.
The earliest known redesign of the turret was dated 7 November 1943 and featured a narrow gun mantlet behind a 120 mm (4.7 in) thick turret front plate. Another design drawing by Rheinmetall dated 1 March 1944 reduced the width of the turret front even further; this was the Turm-Panther (Schmale Blende) (Panther with narrow gun mantlet). Several experimental Schmaltürme (literally: "narrow turrets") were built in 1944 with modified versions of the production Panther's 7.5 cm KwK 42 L/70 standard gun, which were given the designation of KwK 44/1. A few were captured and shipped back to the U.S. and Britain. One badly damaged turret is on display at the Bovington Tank Museum. It had been used as a post-war range target until its historical significance was recognized.
The Schmalturm had a much narrower front face of 120 mm (4.7 in) armour sloped at 20 degrees; side turret armour was increased to 60 mm (2.4 in) from 45 mm (1.8 in); roof turret armour increased to 40 mm (1.6 in) from 16 mm (0.63 in); and a bell shaped gun mantlet similar to that of the Tiger II was used. This increased armour protection also had a slight weight saving due to the overall smaller size of the turret.
The Panther Ausf F would have had the Schmalturm, with its better ballistic protection, and an extended front hull roof which was slightly thicker. The Ausf F's Schmalturm was to have a built-in stereoscopic rangefinder — using twin matching armored blisters, one on each turret side, much like the Americans' post-war M47 Patton tank — and lower weight than the original turrets. A number of Ausf F hulls were built at Daimler-Benz and Ruhrstahl-Hattingen steelworks; there is no evidence that any completed Ausf F saw service before the end of the war.
Proposals to equip the Schmalturm with the 8.8 cm KwK 43 L/71 were made from January to March 1945. These would have likely equipped future German tanks but none was built, as the war ended.
The turret was easy, being that I made the E 50 already, but the hull was not. I'm not 100% on the hull because it seems too wide, but it really isn't, and of course with the front plate how it is I couldn't put on the front fenders without seriously ruining the smoothness of the front plate.
However, I did recreate the reversed torsion bars that the real Panther had as well as the little wheel right behind the drive sprocket that is there to raise the track a bit before feeding onto the sprocket.