block heater for spider?

[James Hamilton Lambert <jhl6d@domain.elided>]

I'd like not necessarily to install a heater element--what device
would work in my driveway to minimize the cold starts. I don't
mind having to lift a heater out in the mornings and don't think
I would take it from the driveway. I have a carport but not a full
garage. Thanks and regards,
Jim 85 Spider, Charlottesville,
VA (also I'd like not to create a fire hazard)

PS With regard to the heater valve and heater fan motors in a spider,
I replaced both (and the associated hoses) last month without removing
the dash. The heater valve was not much trouble (2 hours?) but the
fan motor was considerably more work (10 hours?) for me. I could reach
the heater valve upside down in the driver seat head under the steering
wheel, without removing console. I did not
(because I could not reach them) remove the clips in the back of the
heater-core unit, only in front. I took out the AC ducting in the dash
and did not replace it, also the condenser unit. (I had removed the
compressor unit some time ago.) There is much new leg
room on the passenger side. Access would have been
less without removing AC, not sure if would have been prohibitive. The
new fan was about $130 from IAP, the valve about $30. I drilled drain
holes in the plastic pan under the fan. In fact the fan does not improve
the heating by much if at all
over the natural forced air. Without the fan I am
often closing the valve partially because I get too hot. I also had the
radiator recored (about $300) at a local shop. In the past year I had
replaced most of the heater hose and the thermostat. (I did need to 
remove 
the middle consoles to get access to the heater unit and the fan.) All
the above thanks to this digest for hints and avoiding much potential
trouble. (I am using the magnesium? plug in the block, after one year
the old one had reduced to nothing, from IAP about $20.) 

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