Genprep is what you are describing. For a nominal fee (around the price of raising 6 children) you dealer will take that nice, new Onan 6500 out of the box and in about 3-4 hours it is complete. It just means that it is space available and pre-wired for its installation.
Jim and DW 50 years Brenda
2017 40rssa, also a 2015 Salem (for Alaska)
2019 F450, ruby red
Harley Road King & sidecar