If you need it in INCHES then:
SCALE entire drawing by 10/254
Turn off SNAP (F9)
Using the dialog reached via the UNITS command, change your units from decimal to fractional, with a precision more suiting to your needs, like 1/32 or 1/16 or whatever.
The dimensions will be huge, but you that may not be a problem, depending on your purpose.
Are you just trying to take measurements from this drawing? Are you trying to use the geometry for CNC programming, or what?