I wanted to know how much T'Challa can bench press in the Heavenly Armor, Light Armor, and the Thrice Blessed Armor. If anyone has any exact amounts or reasonable calculations, please share them with me.

Hard to determine. He only wore the light armor twice. Once when fighting Doom and again when he confronted Captain America in the Civil War. In both instances, there wasn't any showings of strength. To my understanding, the Heavenly Armor and Thrice Blessed Armor are one in the same, but still, they've only been wore a few times. Once against vampires, again against Iron Man in the Civil War, and again against Killmonger. Like before, no notable strength showings. But, nothing was ever stated for any of the armors to increase his strength, so I would imagine that his strength would still be the same with either of those armors on. 

Thanks.