If you were willing to spend the coin, a webasto or something similar is the best thing since sliced bread.. I have one on my 01, and I have one for my 93 that will be going on...
I leave it on for about an hour, and it starts like it's summer time out.. no smoke, etc.. if you don't know, it's a diesel fired coolant heater, circulates the coolant around, has a built in pump.. leave it on long enough, it'll get the coolant to and maintain about 170° temperature..
The only con is they are expensive, but you can find them used, and they are easy to work on.. go on ebay, and look up parking heater.. they're big on European cars because many countries over there you can't idle your vehicle..