make a socket from pvc pipe with a slot down one side.. for handle to fit... epoxy the inside to hold a flat bit wood drill bit..  
cut drill bit to length.. and use a battery powered drill.  and same drill for stabilizer jacks with a 3/4 inch socket..
do a search here of photo and directions on the crank handle socket...
I did one 3 years ago. 
NO MOD needed for crank handle
FYI.. Harbor Freight has a power jack for 129 and use a common 20 percent off coupon.  jack is rated for 3,000 pounds.  I have not used one.
DO NOT use hammer drill or Impact wrench.. will destroy gears...   smooth, even power.. or arm power.