I think I've figured out why you & I don't seem to be on the same page - we're actually discussing two different vehicles.
Your original post asked about swapping a J23A from an Aerio into a 1.6 Sidekick/Tracker.
This is not a 1.6 Sidekick/Tracker - and no it is not a 1.6 Sidekick/Tracker with a J23A engine swapped in - it is an SV series chassis, probably a Sidekick Sport - I can't tell you what engine is it, other than it's a Suzuki J series engine - if it is in fact an Aerio engine, it has several parts from either a Sidekick Sport or a Vitara fitted to it, to allow it to function in the North~South orientation.
The Sidekick Sport is not a Sidekick with a 1.8 engine, it is a completely different vehicle, it has a different, wider frame, and it has different suspension, some of the body panels do interchange, but it's a different vehicle.
If you want to swap a J series engine, any of them, J18, J20 or J23 into the narrower Sidekick chassis (the SE series chassis), there will be some degree of custom fabrication - the engine mounts are going to be different, cooling systems are different intake & exhaust are different - there's no way you're doing this by selecting the appropriate Suzuki parts and bolting them together.
On the flip side, if what you're trying to do is swap a J23 in place of a J18, then yes, you may be able to do that without having a welder at your disposal.
Either swap will require a custom wiring harness, and I would not attempt it with an automatic transmission.