Doc here,
There is a "Shade Tree" method I use on Corvettes when replacing the Dreaded left side plugs...If the space "will Almost fit" between the Frame/steering, but not quite, with a standard plug wrench and ratchet..AND I don't have enough room for a LONG 5/8 box wrench from the bottom..
I get a pair of needle nosed vise grips, and snap the porcelain tip flush with the metal plug body..you should be able to get either a standard plug wrench or a standard 5/8 socket to fit then.
Just be SURE it will fit BEFORE you snap the plug..or you'll have a bigger problem than you had..
I know, Shade Tree..but it does work.
Doc