My German Amercian father, who was a very clever IBM engineer for 37 years, once owned a 1964 Ford Falcon that had eventually got some rust on the floorboards.

He crawled underneath the car and fixed it by covering the bottom of them with lots of roofing tar, it worked very well!!!

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1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)