The bulb is simply a load. All you have to do is replace it with a resistor. The 84's have a resistance wire instead of a bulb, since there is no charging light. The value in the 84 service manual is 10 ohms, +/- 1 ohm (so 10% tolerance or better). Replacing a bulb rated for 5 Watts at best, means 5 Watt or better resistor.
Definitely overkill, but it would work, and $0.89 + shipping:http://www.mouser.com/Produ...uhR%2f0DbTCc7inLI%3d