I have what appears to be an early SRW 14-bolt under my '54 1-ton.
This picture shows how it fits. Since the WMS to WMS is wider than stock I see no problems with tire fit on the inside.
Its only a little wider than stock so you will not become too wide if you have a couple inches on each side to spare.
I've not tried duals on this axle, but since the brakes are smaller than the 14 inch originals I would expect even 16 inch wheels to work. You might need longer studs.
Since the center of the wheels is in almost the same location whether running duals or singles I don't think there is an impact on bearings to worry about. However the weight is probably more than double which has an impact on braking efficiency (important) and un-sprung weight (probably not important).
Unless you plan to run heavy loads I don't think the brake issue is a big deal either, but it is worth being aware of.
