In all due respect, you should consider developing a relationship with a local transmission shop. It may not be the last time you have a trans problem.
I assume this is the original stock transmission you are going to replace. If so, it got to 211K miles by being “bone stock”.
Contrary to popular belief, it is not the mark of a “good” transmission, to jerk your neck when shifting. You can alter the controls and some of the parts so that it does just that.
The ideal setup is to have a tranny that shifts as smooth as silk for cruising and a way to have “balls to the wall” performance when you put your foot in it.
If the case of your tranny is not damaged, you have everything you need to begin rebuilding your own. If you are able to remove and replace it yourself, then just take it out and take it to a tranny shop for rebuilding. Specify certain parts or procedures you want done to your trans and let them do it.
Use common sense when selecting components for the trans. Corvette clutches for example are great for a corvette, that weighs 3,000 pounds, but not necessarily the right thing for a 6,000 pound truck.
Five pinions are better than four if you have enough power to need them. Otherwise, they are a waste of money.
All of these different versions of the “rebuilt 4L60e’s” , came about because of the design flaw of the 4L60e, which was it can not take a lot of power without making changes. The 60 in 4L60, stands for the amount of torque it was designed for. Same with the 80 in the 4L80e. I don’t remember the nomenclature right off the top, but look it up when you get a chance.
Anyway, no matter what you do, keep in mind, you get what you pay for in almost all cases. If someone can sell a monster tranny for cheap, they are not making money unless they cut a corner somewhere.
Also, all “speed” parts used in these “special” transmissions, are all “off the shelf” parts available to anyone, including your corner transmission shop.
Just my .02…………….