Useful adapter to make: buy a 1/2" bolt. Grind part of it down to 7/16 and the end to 3/8. Tap threads at 3/8-16 and 7/16-20. Lop off the hex head and grind/tap to 3/8-16. Grind a flat on each side so you can use a crescent wrench on it. The 1/2" middle can withstand funking without bending.