Introduction
If your Jimny has a 1-DIN radio-CD player, it is more or less a simple procedure if replacing it with any other 1-DIN unit of your choice.
However, if your Jimny has a factory-installed 2-DIN-alike Clarion radio-CD player (typically installed from cca 2005 onwards), you are severely restricted in replacement options.
That clarion player can only play audio CDs, and is quite fussy about which ones it accepts.
Replacing the Clarion 2-DIN-alike player
Replacing the Clarion player factory device is not so simple, because the dimensions of the hole in which it sits are not standard.
Therefore, if you install some aftermarket 2-DIN device, it will fit in the hole, but the trim around it will not be aligned. There will be some empty non-trim space around the device.
It appears that kits (surrounds) exist which fill the void around the aftermarket 2-DIN CD players, both genuine kits from Suzuki and aftermarket Chinese-made kits.
Investigate for yourself on this forum and on others.
Upgrading the Clarion player with an add-on
There is a solution to obtain simple and inituitive MP3 playback without replacing the factory Clarion music player.
Installing this simple Chinese-made add-on enables MP3 playback from an SD card, USB stick etc.
It works quite well and is intuitive, just like playing audio CDs from the Clarion CD player. You can upgrade it with Bluetooth handsfree if you want