It depends on which Jimny model you have and which GV. The G16B engine from the GV can be fitted into a G13BB engined Jimny without too much effort. The conversion is pretty much the same as fitting a 1.6 into a Sammy, use an adapter plate, a little messing with one engine mount and you may need to use the G13BB sump with a modified pick up pipe. The Jimny ECU runs the 1.6 OK with the 1.6 injectors but it will be a little rich around 4500rpm.