I've read a lot about Japanese radar capabilities but not so much about where these systems were actually deployed. I know they certainly had a somewhat capable surface search radar system, though they were about 2 years behind U.S. capabilities during the war. I know the vast majority of land based systems were of the air search type. This is not to say that they never employed surface search systems on land but ground clutter (trees, hills, mountains, buildings, etc.) would have made surface search systems less practical than air search systems.
Then again, I suppose it would make more sense to put them right near a harbor with a specific search range/arc where ground clutter would be less of a concern with the level expanses of water. Putting them there however, would be an inviting target for enemy air assault. Even on a mountain top near a harbor would stick out like a sore thumb. Hmmmm,
now you have me wanting to go read my radar book again. Interesting concept though.