Haven't use one of these since road salt was invented. would tie wrap the 120 VAC plug sticking out in front of the grill. Good ones were at least 1KW and were thermostatically controlled. Should have at least a 12 AWG extension cord to plug them in.
Typically plug uses unplated brass prongs, road salt will quickly corrode these, should find a plated plug, also have problems with froze build up.
People that needs these the most live in apartment complexes with the only parking available is on city streets, ha, with my kids in college, sometimes had to park three blocks away. Key start up problems were cause by frost build up in the carb freezing the choke, don't have these anymore.
Use to have only two prong plugs, then the NEC came out with U-ground, the polarized, ha, that doesn't do a bit of good, if a kid unscrews a light bulb and sticks their finger in there, will still get a shock. Only reason why my son's parent in-laws house burnt down losing everything, was their electrical has to be grounded that also attracts lightning.
Really stupid is with electrical receptacles with those push in connectors on the back to make electrical contractors jobs easier. Just a tiny piece of unplated brass is making point contact to a piece of bare copper wire, dissimilar metals that corrode. Houses burnt down because of this, kids had blinking lights in their new homes. That was a job moving all those plug-ins to the side terminals for an air tight connection.
Because of arcing in these stupid things, making arc circuit breakers law, that run around 50 bucks each and lie like crazy they can tell the difference between a brush and a commutator of a vacuum cleaner arcing or in the receptacle itself, but once they blow, have to replace them, so help me, the world is going nuts.
Was in the 80's are wonderful EPA banned electroplating in this country, sure had our headaches in automotive, if we wanted anything plated, first had to be shipped down to Mexico, then China, besides the shipping cost, didn't do a very good job.
Redoing a bedroom in my home, typical made in China vacuum cleaner draws 12 amps, when I pulled the power cord, it was hot. Brass terminals on the plugs can be wired brushed, receptacles had to be replaced. Only 49 cent each for Levitons at my local building supply store, can do this myself. But if you can't, will have to pay an electrician 75-100 bucks an hour to do this, and more than likely, won't use the screws, just plug them in. Really stupid.
Through the grille is customary, tie wrapping the cord to things in the engine compartment that don't get too hot.
The Elantra has a very cramped compartment. I think I can spot the hole on the side of the block where a cartridge style heater (Kat's 11812) is supposed to fit. I can't get my hand down to that spot. If you do install a heater in your Elantra, please let us all know how you did it. I expect to remove right front wheel and maybe the underbody fairing as well in order to plug the cartridge into the block.
I thought about cutting a hole in the plastic underbody fairing (is there better word for this thing?) for the heater's cord to emerge for connection. There are lots of complications to handle and think through going that route. I won't expand on that right now.
Depending on the type of heater installed, may introduce cooling system problems that were not there before, have a check valve that can lock up causing restrictions.
Kids are all gone now, only have a three car garage some had to be left outside. Just installed an exterior outlet, used a DC power plug where it was easy to plug in a maintenance charger to keep that battery warmer. Keeping your spark plugs clean, had no problems starting cars even in subzero weather.
Most recently was a 90 T-Bird, 93 Bravada, and a 97 Ford ZX2. Major problem was brushing off the snow, and with all these cars in my driveway, had to zigzag with my snowthrower.
But with either, have to have a place to plug it in, sure can't do with if your kids were in Madison or Milwaukee, for them, AAA was the answer.