Assembly issue: vwheels problem

Hi I am having trouble getting all the vwheels on my y axises to be “difficult to turn”, to quote the assembly manual, in an equal amount.

On the Y-axis it seems that the rear wheels are tighter than the front ones, with the rear left being the tightest. (viewed from the perspective of standing facing the machine with the router closest to & facing me). I have tightened the front wheels to their maximum using the eccentric nuts because they are consistently looser than the rear wheels (which are directly beneath the x gantry) but they remain easier to turn than the rear wheels.
Am I doing something wrong? Being too picky? I have followed the assembly instructions carefully, and everything has proceeded well up to this point, which is the moment I want to screw down the machine to the base. Instructions indicate I should tighten the wheels before mounting, and Im stuck here.
Any advice for a non engineer nerd who always reads the manual before taking anything out of the box? Im stumped.

It took me about an hour to get the V wheels set. I ended up setting them just to the point that I could barely turn them. I ended up tightening up the front ones (Closest to you) first then adjusting up the rear ones to match as close as I could. I had to loosen off the front ones a bit but ended up snugging them up slightly in the end. After about 5 months of use I had to adjust them again. Good luck with it as it can test your patience. I found that small adjustments were the way to go. I always had tension on the Ellen key, don’t let it get loose and sloppy as that brings you back to the beginning of the adjustments.

Thanks for your quick advice. I have everything tightened up now, theres nothing left to tighten and it still is looser on the front wheels than the back ones.

Im still wondering what im doing wrong. Did I assemble the x-gantry incorrectly? Is this the correct orientation of the extra rail on the x-gantry?

At this point, Kelly in tech support is sending me 19.5mm replacement v-wheels. I think mine are 19.4mm because Ive been experimenting with the machine for the last month… Ive seen a fair amount of grunge left by them on my v-rails.
Since my existing vwheels are 19.4mm, and my v-rails are only 71.2mm instead of the nominal 71.8mm, i think its highly doubtful that the replacement vwheels will help, since they will wear out with use in short order even if they fit in the short term… I would be forced to replace them as soon as .1mm has worn off.
I am currently asking them to replace the v-rails with the proper size.

They sent me new vrails for my vaxis problem which seems to have solved it.
Thanks to Kelly & Patrick at Sienci support!