Boy you need to be careful with the ether. I've seen some real carnage when too much is used. As far as heat I always liked the waffle iron magnetic heaters. Super simple and you can't beat the ease of install. I used them all the time in the material handling equipment world.
Mark
Ether itself is not the problem, as it is simply a combustible fuel with a lower ignition temperature than the diesel that is also being injected during a normal cold startup. It is its misuse that causes the problems...
Diesels don't have throttle plates and use governors to control fuel. When you fill the entire air filter and intake pathway with a combustible air-fuel mix, when it does finally fire, the engine tends to runaway as you have no control over the engine using that fuel-air mix. So you take a cold engine from crank RPM to redline and beyond, and depending on the length of the intake, hold it there for a bit.
Since the governor is commanding idle fuel, as soon as the RPM goes over idle, it then cuts the diesel being injected so no top end lube either... Its that cold high rev that does the damage, causes the wear that brings on difficult starting, and "ether addiction", and under extreme cases, bends/twists cranks and throws rods, thus giving ether its bad rep. It is not the ether itself...
Direct injection into the manifold like the LMTV uses, is the proper way, it is metered and can be completely controlled, so no runaway, no governor fuel cut and no damage, just the chemical "spark plug" cold starting aid it is intended to be...
