what Danny said big stack height on a pig headset, although steerer lengths can vary a bit,
got two sets of ns Blazer forks mk 1 and mk2 with 18mm difference, the shorter ones mk2 are supposed to be "the perfect length" obviously i'm not using the "perfect" frame with the mk2 cos it is to short , have to use the headset with no top cover on to get the stem to clamp without closing up at the top, is the headtube on the Pork long? may have to be 2hip forks with a longer steerer?
steerer on the GT Pacmans ive got ( 2001 ) is 170 mm to allow for the cups not that it helps much