just bought a 90 crx hf with a blown rod. we had a d15z1 block sitting around. we're trying to swap just the block. we encounter a problem when the timing belts wouldn't fit. the stock d15b2 belt is longer and the d15z1 head seems taller (vtec head). what do we need to do in order to put the stock hf head onto the d15z1 block? water pump, tensioner, belt are different.