“The Wicat is one of the first (perhaps even the first) computer to use a Motorola MC68000 processor.”
That page says this system was released in 1981.
https://en.wikipedia.org/wiki/Sun-1 and https://en.wikipedia.org/wiki/IBM_System_9000 both are from may 1982.
Apollo/Domain DN416 also is in the race, but I couldn’t find much about it, other than that it was a dual-CPU system, using the second CPU to implement virtual memory (https://en.wikipedia.org/wiki/Apollo/Domain#Models: “This system used two 68000 processors and implemented virtual memory (which the 68000 wasn't theoretically capable of) by stopping one processor when there was a page fault and having the other processor handle the fault, then release the primary processor when the page fault was handled.”)