The 2.8 and 3.1 are a much smaller engine
package, I would think a 60* V-6 is more
to the size and fitting in a SideKick/Sammy
engine bay, as well as the weight factor.
Also the 4.3 is a lower reving engine, it is
based on the 350 V8 but has 2 cylinders
removed, the 60* V6 is a different block,
and is supposed to fit into a 15x15x 20
inch space, without accesories. One of these
little, yet potent engine packages should
give you plenty of grunt
My .02
Wild