'88 van, no leaks, new thermostat--wrong size?

Disappearing water came from overflow bottle because of bad thermostat.
While I was visiting my new grandbaby at the hosp. my daughter's friend decided to surprise me by putting a new thermostat in. It was installed when I got back, but it's for a 6 cyl. Really sweet idea but I only have 4 cyl. Will it work or do I need to replace it?

it'll work.
Should be about the same temp, too.

Yeah it's probably just a normal 180 F thermostat...