You are right. But 减GST或者减 personal income tax is totally different. I'd prefer 减 personal income tax because I'd have more money in my own pocket that I could have control by myself.
But I don't feel that you guys should get such impression that conservative will only cut 2% GST. I feel that will cut income tax as well. Their promise of cutting 2% GST seems more reasonable to me. As liberal promising to wipe GST out, but later never keep their promise after being elected. So don't trust those promises which sounds too good to be true.
Also don't get such impression that liberal intends to cut income tax. They only proposed this in the latest budget before election and the intension is very clear, buying your vote.