Things like fuel pump and vac advance diaphrams, not to mention things like all the rubber and neo on the vehicle get really dead really fast with varying temperature. Add to that if you have a need to do any professional grade painting with air minus any water, I feel its very important if you are restoring to keep the temperature at 75 degrees plus 10, minus 5. Most paint applications don't work well at less than 70 and the results are very iffy above 90. So, if you have a connected 2 car garage, insulate it very well, then run large ducting from your home heating system to your garage, but without a return. Its not ideal, but unless you want to spring for a second heat/ac system, it will do the job.
Be careful. VERY careful when painting and using a kerosene heater. Careful meaning, don't even think about it. Any open flame when restoring is a bad idea. From gas, to laquer thinner, to highly explosive paint and glueing operations, there is always a reason to keep open flames away.
If you decide to use a wood stove or kerosene, just make sure your life insurance is up to date so your wife can at least rely on that.
