The quality of early Heng Long products was very dodgy, improved no end now. I have a Pershing, the Grandchildren love it, as I do,lots of faults in detail (Pershings were rough cast hulls, not smooth, but who cares!!) I took the Yank Commander out and with some filler and paint turned him into a Brit, complete with Beret and Tank Regiment badge! Somewhere ,sometime ,maybe some Brits drove Pershings! When equipped with the British 17 pdr gun, they were "Tiger Killers," and were very effective, had a long history, served in Korean War as well.
If you want 1\16th scale bits and bobs for them, try Imperial Models here in Germany, they have loads!! Even do an exchange service for Gearboxes etc. Speak English, worth a try!