  We reconsider the dispersive evaluation of the weak matrix elements
<2pi_{I=2}|Q_{7,8}|K0> in the chiral limit. The perturbative matching is
accomplished fully within the scheme dependence used in the two loop weak OPE
calculations. The effects of dimension eight (and higher dimension) operators
are fully accounted for. We perform a numerical determination of the weak
matrix elements using our dispersive sum rules fortified by constraints from
the classical chiral sum rules. A careful assessment of the attendant
uncertainties is given.
