To continue from my last post ----- Surely you can't be unlucky enough to have a seized engine as well as having a faulty starter (and as well as perhaps having a faulty alternator)!!!!!!!
I suspect "nothing more happens" because your 50 terminal has been pushed inwards by "shipping damage" to stop your plunger from completing its travel.
Hold it here Albert!
This last sentence implies that your "50 terminal" has indeed been knocked inwards and needs to be pushed back out to its correct position so it no longer interferes with the movement of your plunger (before you use "JB Weld" to secure it).
As mentioned above, it sounds like your "50 terminal" has indeed been knocked inwards and needs to be pushed back out.
It is a "magnetic thing".
When current flows through both the "pull-in" and "holding" coils - those coils become "energised" and thus exert magnetism to draw the plunger towards those big electrical contacts Albert.
Well I'm a 56 year-old weakling so you must be able to muster more force than me (and I can turn mine).
Like you, I also find it hard to believe that your engine could be seized without you being aware of a cause.

....bench test ...was unsuccessful.
...the 50 terminal .....touches the housing as soon as the starter engages and nothing more happens
I suspect "nothing more happens" because your 50 terminal has been pushed inwards by "shipping damage" to stop your plunger from completing its travel.
....I was only able to get the starter to pop but not spin....
.... The inside of the 50 terminal interfers with the operation of the plunger......
....Comparing the old and the new starter, the old 50 terminal is shorter on the inside........
Hold it here Albert!
This last sentence implies that your "50 terminal" has indeed been knocked inwards and needs to be pushed back out to its correct position so it no longer interferes with the movement of your plunger (before you use "JB Weld" to secure it).
....I placed the plunger back into the starter and pushed down on it and it will not go down towards the contacts without touching the insde of the 50 terminal. Could this be??? Am I just unfamilar with this or is it possible that this starter was never tested properly?....
As mentioned above, it sounds like your "50 terminal" has indeed been knocked inwards and needs to be pushed back out.
...I would like to use JB weld to hold the terminal where it was based on the inside position of the plastic housing around the 50 terminal on the inside. I could then try another bench test BUT, if I were to do that, should the plunger be below or above the 50 terminal? House does the plunger work? Does it need to touch the contacts to move up or down or is it a magnetic thing? ...
It is a "magnetic thing".
When current flows through both the "pull-in" and "holding" coils - those coils become "energised" and thus exert magnetism to draw the plunger towards those big electrical contacts Albert.
...Regarding turning the engine, I have not given it another try. I'm hoping I can't turn it because it requires more force than I can muster. I will purchase a shorter 1/2" ratchet to see if I can give it another turn. Also the ratchet I was using interfered with the fan blades because I was only able to use it with the handle facing the passenger's side pulling UP on it until it got close to the fan blades. My tool would not fit in any other position....
Well I'm a 56 year-old weakling so you must be able to muster more force than me (and I can turn mine).
Like you, I also find it hard to believe that your engine could be seized without you being aware of a cause.
