Would it be a bit easier to convert to a live axle at this point, I know price wise, no, but if if he went with pillow block bearings, it would cut down the amount of welding needed, and 2 is always better than 1.
If it's financially viable, I'd say go for it. Just let's keep in mind that it has the potential to be costly. Requirements may consist of:
*Axle shaft
*Bearings- either pillow blocks or flanges, and some steel for mounting
*May require a new sprocket and/or hub to mount directly to axle
*Wheel hubs and/or new wheels
*New hardware to mount brake to axle, or possibly new brakes.
This is a general list, including SOME possibilities. It is not necessarily a complete list, and some things will depend on your individual application, resources, and ability.