Is the clearance issue really an issue? Some food for thought.
In the 1953 NEC the minimum horizontal working space clearance is given as 1-1/2 feet, measured from the live parts to a not grounded or live surface.
In the 1975 NEC, the same conditions under 600 volts was
2-1/2 feet.
It wasn't until the 1978 Edition of the NEC that it was increased to 3 feet.
