Before you do anything with the injectors pull the valve covers and pull the solenoids off a couple. Measure the armature clearance. It should be .002" -.004". .004" would be prefered. If they are below .002" don't bother having them rebuilt. They are about worn out and while if you know what you are doing to can bring that tollerance back in spec. you can NOT actuall fix the problem which is the worn out popit valve and seat. If the clearances are good then send them off to someone who can properly rebuild them and flow them to ensure they are working properly.
Stage Is and Stage IIs flow the same amount of fuel. So the fuel requirements will be the same. Your stock system will be running at it's limits to keep up but if you aren't rodding on it constantly you'll probably be able to get away with the stock fuel system. Hook up a fuel pressure gauge to monitor it when at WOT and that will tell you if you need bigger or not.
A complete bigger oil system isn't really needed with the stage I or IIs depending on the condition of your pump. A 17° pump would help and would most likely be enough to maintain the pressure you need to keep from setting a CEL from low ICP.
Your tranny won't last long with either but will last a little longer with the Is. I wouldn't bother installing a valve body in it because it will go regardless and will get all new parts in the valve body when it gets rebuilt so I'd just save the money for the rebuild.
Your turbo is also going to be hurting if you rod on it a lot too. If you keep running it over 30 psi regularly it's not going to last long. If you keep it under 28-30 psi it will last a long time.