Jet Drive Under water hardware eg; Loader and shoe ,shoe dept and intake opening etc including "ad/ subtract" changes modifications and the like ,IOM can only be effectively and properly done by "test & tune" with intake drilled tapped and equipt with pressure guages for comparison readings and data.
None of this is "plug n play" ,admittedly there will be recommended "starting points" according to Boat type and bottom style , intended useage, HP, what impeller and on and on... its all an experiment.
Nothing will ever prove to be optimum with out experimentation! ,one will never know that without comparisons and trial error.
Post up as much info as possible to get started if you need help !
Tom