Talk to the ppl you brought the cams of in regards to whether they want both cams returned or just the one ..
i had the same concern as your sell as to which cam to buy for a series 2 25t and going by the spec's on the years for the cams you needed to buy the series 1 cam because of the crank angle sensor drive change later in the 97 onwards range.. Not 100% sure if there is difference's in inlet cam's for different year models but just ask them..
brought hks instead and thankfully i ordered to correct ones and they sent the correct ones . cas fitted perfectly ..