2 x 0.047 uf caps across the terminals?
2 x 0.047 uf caps across the terminals + a 3rd 0.047 uf cap wired in a triangular link to the motor case??
Probably should read "1 cap across the 2 motor terminals or 1 across the terminals plus another 2 in series with the connection between them to the motor case."
I find that 1 across the terminals does the job. Using the other two is basically just adding an extra and doubling the value but with the faint possibility of adding an extra fault liability. Extra wires = more chance of a short. If one of the extra capacitors disconnects there is a theoretical chance of an unbalanced circuit which can, theoretically, generate interference. The theoretical chance of this is about the same as the theoretical chance of the extras doing any good in the first place.
If the capacitor leads are too short to reach, just solder a short (but long enough) length of tinned wire to each of the motor terminals (wrap and solder) then solder the capacitor leads to the tails. Paint with nice thick varnish to keep it insulated.