Members of the Senate Finance Committee yesterday voted to amend the tax package by adding in pension simplification provisions originally left out by committee Chairman William V. Roth Jr., R-Del. The amendment, a bipartisan effort introduced by Sens. David Pryor, D-Ark., and Orrin Hatch, R-Utah, passed on a voice vote. Similar provisions were part of the tax bill approved by the House Ways and Means Committee last month. The bills now go before the full House and the Senate, which are expected to vote on their respective bills next week.