Also keep in mind that N15 radiators come in small and large cores:

From: 320 x 535 x 16 mm
To: 320 x 647 x 32 mm

The smallest N15 radiator is used with GA16DE engine. The largest N15 radiator is for Diesel and SR20DET.

The stock A12 radiator core size is 330 mm x 344 mm x 32 mm, so you will probably have to cut the body sheet metal core support and use the stock N15 fans to make the N15 radiators work correctly with a 1.5 liter engine.

N15 radiators come in different flavors including core sizes, different thicknesses, and either 28mm or 35mm inlet/outlets.

Radiator Upgrades has a bunch of information on it. Click each photo to get additional details.