I mentioned I would get back with you, and Rick (titan1a) sort of beat me to it, but yes I would use a solid state replacement tube for the 6X5. Must easier than adding diodes and resistors to limit the inrush of current, and to me using bulbs would be out of the question. The inrush would cause the bulbs to flash bright when first turned on, probably in time, if not right away burning them out. Also the belt kit is available through radiodaze, and using this you don't have to disassemble the entire tuning shaft. I used this on Ricks radio, and it has worked fine for over 8 months or more. Just cut the belt to the right size, so that it has some stretch to it, and glue (with the provided super glue) it and once dry, slip the belt on. Yes, It will hold. Link for belt kit below. Also below is a link for the solid state plug in rectifier. Simple and easy, just pull out the old tube and plug in the new solid state one. No wiring, no messing with resistor values, diodes, etc. Links below. Hope this helps you. Rick has had absolutely no problems with using the 6X5 solid state replacement or the belt. Yes, it might cost a bit more, but it's worth it
http://www.radiodaze.com/dial-belt-kit-6-foot/
http://www.tedweber.com/wx5