Apparently, Pepsi and Walmart have taken delivery of a small number of these tractor-trailers. Considering they were announced in 2017, production is way behind schedule, and I am sure Elon's Mars landing will be farther in the future than he is predicting.
The thing about these trucks though, is that even if they were in production, charging them will be an even bigger problem. An entire separate network of truck charging stations will need to be built with a supply of gargantuan amounts of electricity. I'm not holding my breath.
Elon Musk has many talents, but I do not believe he has any sense of irony or mortality. He thinks it would be "cool" (what ever that means) to die on Mars. Barring any unforeseen accidents or illnesses, he's got about 40 years max. It's not going to happen at this rate.

The truck -
https://www.youtube.com/watch?v=Uv44W7xa4IU

There is a coy in brisbane who convert Prime movers from diesel to electric.

The running costs of an old diesel is huge.
The price to fully renovate an old prime mover diesel is enormous.
The transmission has had it's life by then.