The pin the throttle should be at the back end of the slot in the kickdown lever at idle. As soon as you accelerate, it increases the throttle pressure and shift points. Wide open throttle should get you wide open on the transmission lever.
Wal Mart battery here. Inexpensive and it has pry off caps and a black case. I dressed it up with one of these kits from Weskcar.
https://www.forabodiesonly.com/mopar/threads/mopar-battery-dress-up-kits-and-cap-color-chart.463428/
My point was why does it matter who makes them or where they come from as long as they are correct. Another point is the suppliers aren't going to let you in on who makes them for them. Most aftermarket parts are made buy just a select few manufacturers overseas. Everybody buys from the same...
Good luck finding out. The resellers don't reveal their sources. There may be a dozen manufacturers or just 1 or 2. 99% chance they are made in China like most repop parts. Next question, why does it matter?