Cone Air Filter Maf Adapter - All The Same For Nissans?

[GripSpec]

I am a long time 240 owner but a new 1994 G20 owner (sr20de). One of the only issues the car has is the fact that one of the previous owners removed the bottom of the airbox and it now only has the air box top with a dirty filter ziptied to it. Not really my thing so I figure it would be a good time to put a K&N or something decent on there. I have seen metal air filter adapters for older nissans but am not clear on which adapters are interchangable. Are KA/SR20det/SR20de filter adapters all the same? also does anyone know where to find one that would fit a decent filter like K&N?

[Spring Break '92]

Yes, those would all be the same. The only different one is the adapter for the V6 motors, i.e. the Z32 MAF adapter.