That's the "butcher" way to do it.
At least one radio amateur reverse-engineered the set's PLL/Counter programming and came up with a way to add 27-27.5MHz to the set's Aux band position. Using the programming example as a guide it's also possible to add other ranges. An ongoing effort to make use of the "+0.5" switch is also underway and according to the author should be completed soon. A Net search will give details.
FWIW, this is also applicable to the TS-830 series. When done the set would cover 27-30MHz continuous with a bit of overlap. Perfect for some models of transverter whose IF was 27-29MHz.