Since you're asking about the Sidekick, I'm going to assume you're in the USA.
The Sidekick is what is commonly referred to as first generation or SE series - it was only available with 1.3 & 1.6 litre four cylinder engines, and the 1.3 was only offered in 1989 - there was also a Sidekick Sport offered from 96~98 with a 1.8 litre four cylinder , but, although this looks very similar to the smaller engine Sidekick, the resemblance is in the bodywork, the underpinnings are different - this is the SV series.
Outside of the US, where the Sidekick was sold as the Vitara, the SV series was offered with 2.0 litre four cylinder & V6 motors, but the US never got these models - the 2.0 four cylinder is essentially the same motor that was fitted to the US market Vitaras & Trackers from 99~03, and should be readily available - I believe this is a relatively easy swap, and a couple of the Suzuki specialist vendors at one time offered kits to do it.
Moving on (or up) there were also 2.5 & 2.7 litre V6s offered in the Grand Vitara and XL-7, and I have seen those dropped into the SE series chassis, but, there is apparently a lot of work in sorting out the electronics, especially as it relates to the 2.7 engine.