[Arran]

Given the way the line caps are wired, and that it is an A.C set with a power transformer I don't think it will matter which side is switched like it might with an AC/DC set. I'm not sure what are the largest values available in X and Y rated capacitors, but the purpose is to suppress noise coming in from the power line, so smaller caps might result in more noise, but then again larger value caps may result in more A.C current leaking to the chassis, though not like it would going from a .01 to a .2 uf for example. A lot of sets don't even have power line caps, like RCA (and Canadian G.E sets) have an electrostatic shield wrapped around the outside of the windings of the power transformer, and grounded to chassis.
Regards
Arran