Driver bushings

[nachoman]

I'm thinking of re-working an old Mantua General, but using different drivers. I am assuming the General used 1/8" diameter axles. The drivers I want to use have slightly smaller 3.0mm axles. Any thoughts on putting a bushing somehow or taking up the extra space in the axle slot? I think we are talking about 0.007" difference. I suppose another option is to make new 1/8" axles and turn down the ends to a smaller diameter to fit in the wheels.