The extra-long Willys is a jeep manufactured by the American auto company of the same name. This off-road vehicle was very popular in the 1960s and 1970s.
You mean very long. Too long, large length. Exaggerated length.
I'm not sure it exists. At best it will be a neologism formed by extra- ( "out of , excessive") long ( "length extension") , such as "very long, extremely long".
EXTRALARGO longer than standard or normal. Some synonyms, words or similar expressions can be extralarge, xl, extra lungo