I will answer what I know. Hopefully someone else will chime in with the rest.

Also if I found the 1.6 and it didn't have the head would mine bolt up?
It can, it has been done a few times. There are some caveats that I can't remember off the top of my head.
If I am able to run my head on the 1.6 block this means I can stick with my carb and I won't need the electric fuel pump right?
No, you will need an electric fuel pump. The 1.6l does not have a manual fuel pump so something will have be be installed. But you won't need a high pressure pump, so you can get a generic electric one from your local auto parts store. On my old SJ I mounted mine in the back where the fuel filter normally sits.
IF all of my assumptions are correct I shouldn't be getting into too much wiring correct? Just a bigger Alternator and Starter?
Same starter, since you will be using the adapter plate.
What years sidekicks/trackers should I look for to get the new motor from?
It needs to be an 8valve. So pre-94 2-doors and 91 or 92 4-doors.
And one more, the big one, what kind of difference would I see in the power? Speed wise that is
The 8 valve is rated at 85hp compared to the stock 1.3l's 65 hp. But your going to loose a bit of that dropping to the carb setup. But even 10 hp is a 15% boost in power.