There are adapter kits available that will allow you to use the newer style injectors in your older style fuel rails, and it will also come with the pig tails to update your injector connectors. As far as grinding the plenum it's only for the number one injector and that grinding is way easier than removing the plenum again to replace an older style injector(s) which have a super high failure rate because of the ethanol mixed in the gas. The newer style injectors address that issue and use a pintless style design which is better inmo.