Skull Crusher,
I agree about the engine case mounted sliders. Bad idea.
The AxlJack seem to be beautifully made (if a bit pricey), but the front slider is set so high, it appears that the motor cases would hit before the sliders. Do they rely on the rearset footpeg to protect the cases? They certainly look strong enough.
I fabbed my own, and set them lower;

I've tested them, they work.
Best,
Redhawk