Carb questions

Want to run a 24mm delo Phbl on a standard Indian gp200.it doesn't fit the standard manifold with carb rubber I have.
Do I need to change the manifold or can I get a carb rubber that will fit.which manifold do I buy and also what jetting should I use with a clubman exhaust.cheers
Do I need to change the manifold or can I get a carb rubber that will fit.which manifold do I buy and also what jetting should I use with a clubman exhaust.cheers