If you can't afford downtime then just buy a spare block/crank and then sell your current block/crank when you are done with the swap.
Instead of TT rods, I'd look into the lightweight rods from
Blueprint Manufacturing - Quality Performance Parts . They should be about the same cost.
Add a set of ARP rod bolts as they are the weakpoint in the bottom end.
Its been a while since I've researched d-series bearings, so use whatever works for you there.
You mentioned vitara pistons, so I assume you plan to boost.
You will also need new gaskets. Might as well go ahead and tap the oil pan for your return line while you are at it. Add in some baffles in the pan as well. Get a new oil pump. Consider getting it ported by
The Old One - Energy Dynamics .
Also get ARP main bolts as well. You want that bottom end buttoned up as well as you can get for a reliable build.
Also a good time to drop in a better radiator. If you don't have A/C, then go ahead and get a full width radiator (good if you plan to boost), or just get something like a delsol dual core rad, or an aftermarket aluminum rad like the mishimoto, koyo, fluidyne, etc.