The Audison Prima AP 4 (midwoofer) and Audison Prima AP1 (tweeter) set, with proper placement of the tweeters on the dashboard, transformed the terrible factory sound of the Jimny into a very decent and clear sound well above the levels I initially expected.

As a source, I use a slightly above average 1-din Kenwood KMM-BT305 with its internal amplifier.
With a few relatively small amount of money, the tiny but very capable 4x4 became a beautiful melodic environment.