Fender Truss Rod Washer Size?

musicalstash

Does anyone know the washer size needed  to shim a truss rod in a mexican reissue stratocaster .

The guitar has a bow in the neck with the truss rod maxed out and thought I would try a few washers before tanything more extreme but not sure what size is needed.

I know Fender used to sell them but the only ones I have seen have been the nylon type and only for basses( I have the same issue with a Mexican Precision bass ).

thanks in advance