The 4l60e has a couple of different plate gaskets. If the kit was for a 98 you're good. The change was in 2001 again changed in around 06 but not exaclty sure on the date. Most kits come with 2 sets of gaskets, use the ones without the white or yellow line or the ones that have 1 letter ( C for case and V for valve body) .
Pumps go from 7 vane in the early 700r4 up to 86 then to 10 vane up to around 97, but have seen some 96 pumps that are 13 vane , then 13 vane that doesn't pump anymore fluid but keeps pressure from fluctuating but are weaker because there are more cuts in the rotor to accommodate more rotor blades. I have put 10 vane rotors in a 13 vane pump if I knew the person had some power and a high stall because they didn't want to buy a new 100 dollar billet rotor ( Which most of the time is a 10 vane anyway )