I haven't looked at the Si system, but it's possible you need the Si rack to use the Si's electric pump. I really don't know though, it might be possible?
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Andy - Reinstated
Hybrid Forum Moderator
'06 Subaru Legacy Spec B - Stock, for now
'98 Civic EX - CTR headlights and grill, Kosei K1's, for sale
'90 240SX - SR20DET that will never get installed, project car.