I had exact same issue. I fixed mine with these : https://smile.amazon.com/dp/B08DJ76YXG?psc=1&ref=ppx_yo2_dt_b_product_details

Be aware, I think you posted a link to the wrong size. You need T8x4 @ 2mm Pitch, 2 Start, 4mm Lead. The plastic ones will have less slop until they start wearing down.

I've always used lube...it didn't help with this issue but you should definitely use it on all applicable parts. I used https://smile.amazon.com/gp/product/B000UKUHXK/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

The ptfe keeps it in place longer. I just ran a line down my lead screw on the side then moved the bed up and down.

In regards to getting the stock nuts off...you can do it with the bed still attached. I just did it. You just have to take off the lead screws and prop the bed up.

No downsides. Only other thing I will note is how much I love being able to run G34 to level my bed on the two z axis's. Not sure if the stock board supports that but figured I would mention it...you have to level the two lead screws.