If the police had a device that enabled them to see into car trunks, it would likely constitute a search requiring "reasonableness" to use it.
"Parallel construction" is a message board argument. At the point where you've decided the law doesn't matter, we can just stop talking about this stuff, because none of it matters.
https://www.reuters.com/article/us-dea-sod-idUSBRE97409R2013...
It seems very unlikely that anybody parallel constructed anything here, since an officer was able to see the guns with the assistance of a visor made of his fingers.
It could simply have been in a car accident and its driver taken to hospital. It may even have been off the road by the time it was towed to the impound. I see this happen several times a week.
I would have not been happy if that was searched and inventoried.
Does the expectation of privacy go up and down depending if the mobile home is driving?