I can’t speak about the port match between the LA intake to the Indy head, I can tell you that the Indy heads ports are larger and the attaching bolt holes are wider by a little bit that you will have to redrill the intake to match. The best way to go about this is to weld up the intake and re drill it.
While you could use a die grinder to oval out the bolt holes as a quick way to get the intake to bolt up, it is a spot that could be a source of oil leaks. A bit of RTV is a good thing to use on the intake bolts to seal up any possible leaks for any application, the wider hole will make any leak a big pain to deal with.
I am not sure if a port matching can be done. The Indy heads ports are still rectangle but not the same like a stock port. This could be an issue requiring epoxy to get it to work best.
What intake do you want to use?