get used to it???
I had a friend who bought and restored an old VW Beetle,that mice had taken up residence in...after ripping out the headliner(it was sagging due to 10 lbs of mice nests and poop!~

)and the seats,he used a "steam jenny" at the bus company his dad worked at to steam clean the entire interior with high pressure water and detergent...it still reeked a bit,but nowhere near as bad as before..the seats got the same treatment,but were found to be the main source of the odor..so he bought used seats at a swap meet that didn't stink...
Mostly its carpet,cloth seats,and the stuffing in them that retains the odor the longest..might have to rip them all out and replace them...
If you pressure wash it,a long drying time in the sun is best to get the odor out as much as possible..we had to de-odorize a lot of cars we sold at the boneyard..nearly all had some kind of critters living in them somewhere!..(dead frogs in a pool of water in the trunk of a 55 Buick were THE worst smell my nose has ever inhaled!.

..PHEW!!!)..--Mold and mildew stink bad too--we had mushrooms growing in the rugs of many cars in the boneyard!!--we bought lots of those "Christmas Tree" air fresheners!!..
Its a difficult smell to eradicate---(urine of any kind is,but mice seem to have THE worst ammonia piss on the planet)..I know one guy with a grudge against another guy who slept with his fiancee,who poured a one gallon jug of piss he saved in a milk jug for a month,down the louvers where the windsheild wipers park....they ended up junking the car after several attempts to "de-odorize" it!..

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