[Christ]

Have you actually checked to verify that you have front output when in 2HI mode? Most tcases do not.

The 45mph recommendation is a NHTSA/Auto Mfr recommendation based on the fact that if you needed 4wd, you probably shouldn't be going more than 45mph anyway, not to mention that tire slip increases at higher speeds, and true 4wd systems don't steer well when in use, thus making a very dangerous situation at higher speeds. It's just plain unsafe, and there is no discussion necessary on that topic.

The shorter ratios, I was wrong about. They would mean nothing in your case, since you're driving on a 1:1 ratio from front to rear output shafts.

In most cases, 4Lo is not recommended for use on any surface that isn't soft. As such, you shouldn't be outside of low gear when using it.

These really shouldn't have to be discussed... talk to a few offroaders that have had to limp home on FWD only, and you'll figure out that they're practices that should be adhered to fairly well.

The speed limitations for 4wd mode don't apply if you're using the motor in place of the front axle connection, because you won't be turning all 4 tires under power, so you can disregard that part.

Mounting the motor inline with the rear driveshaft DOES NOT subject it to suspension abuse. I'm not sure where you came up with that...

Using that configuration would also allow you to remove the motor from the driveline by removing a few bolts and replacing the original drive shaft... not sure how hard you think that is, but if you find it difficult to R&R a driveshaft with a carrier bearing, you probably shouldn't even be thinking about this type of mod.

Mounting it from the front input of the xfer case does not give you a "gear reduction for low speed use." as you'll be driving the rear shaft at a 1:1 speed through the xfer case, no matter what gear you're in, unless you have two differential sizes in the front and rear axle, which is highly unlikely. If both axles have the same differential speed, you'll have the same 1:1 ratio in the t-case no matter what range you select, as this is the nature of 4wd... turn front and back so they match each other based on the engine's input...