Well, it took a while to get back on here and post due to work, etc.. - but for anyone who still cares, I finished installing my Misumi bearings and rods. The machine is now definitely quieter than it was with the stock pieces, not silent by any means, but noticeably quieter.
Not being a mechanical engineering expert - just visual comparison of the stock and Misumi bearings seem to be very similar. The difference on the rods was very noticeable though - the surface of the Misumi rods compared to the stock was definitely far more polished/machined.
For the bearing attachment to the Y carriage I first printed and tried to use these, https://www.thingiverse.com/thing:1848700
, but as soon as I would begin screwing the M3 bolt in they would start to have a slight crack/separation running along the layers due to the orientation they must print. The holders print so that the layers run parallel to how the bolt runs. Maybe it was my print settings and/or the filament I used, but I did not feel confident in using these and did not want to be taking it apart again anytime soon. So I went with a much more secure method that I had to fabricate. I used metal pipe straps exactly like the ones in the picture. It was a bit of a pain because there was a lot of trial and error and detail work but it is worth it knowing those Y carriage bearings will not be wiggling around! Which by the way, the zip ties had definitely loosened up/stretched and were allowing the bearings to have movement. I would flatten out each of the metal straps and then cut them off approx where the red lines are and then drill new holes where the green is to line up with the holes in the carriage. I also had to polish/clean them up on the grinding wheel to get rid of any burs, sharp edges, etc.
In the second image(the crude drawing
) I show what this looks like on the carriage with the black being the carriage and bolts, the green being the bearing and the red being the metal strap. This holds them VERY securely. It took a little back and forth tweaking to get the clearance exactly right with the bolt head and/or nuts so that it cleared everything properly but i think it was worth it. Sorry, I do not have a photo with me to post of the finished attachment piece but I'm sure you get the idea. I used M3-0.5 x 22mm bolts and had to do a little grinding on the end of the bolt to make sure everything had plenty of clearance.