Air cleaner assembly /heater core

I need to replace my air cleaner inlet tube and vacum motor tube because I have them on with duck tape on my 1986 2.3 mustang but Im having A hard time finding one that is not in the same shape as mine ,they always seem to rip at the end of the inlet tube ,for some reason they used this paper thin crap to connect the inlet tube to the vacum motor in 86,so what are my options ? I cant just get rid of the whole thing because then it wont pass emissions !


My 86 has a/c and I need to replace the heater core can I go through the glovebox or do I have to remove the dashboard ?

will A k/n filter give my 2.3 more horsepower or not ?