do it... its fine
the general rule of thumb is 4" +/- rim to tire width, but there wont be a problem with what you are proposing.
i mounted a pair of 33x12.5x15s onto 15x6 rims for a customer on their toyota in years past, they fit just fine.. being a 35, will actually put less leverage on the rim, making it even better
it will also help hold a bead better
