ShakeZulla

Hey guys I have some questions. I rebuilt my motor and went to some performance parts and I am wondering what will optimize my parts. Here is the breakdown of what I did.
-pistons, rods, rings and bearings - block machined and balanced
-performance head with 280\440 camshaft (link http://www.22reperformance.com/22RE%...r%20heads.html)
-adjustable cam sprocket (went to double chain)
-2inch exhaust
-injectors cleaned
-high flow oil pump
-high flow rocker assembly

I also replaced the following...
-water pump
-clutch
-head bolts
-all timing components
-cap, rotor, wires and plugs

Then I tuned it to 5* according to factory specs and failed emissions testing. Then I replaced...
-O2 sensor
-TPS (also set Idle screw to fac spec and adjusted TPS correctly with ohm meter.)
-Made sure the MAF flapper was closing all the way.

I still cant pass idle on emissions but I'm close, 2500 rpm passed. I was able to prove that I spent over 300 bucks on the truck so they passed me but my questions are as follows...

1)To be able to get to factory timing I had to retard timing on my adjustable timing sprocket even though the chain was set right. Is this common with a cam like this?

2)What should my timing be with these mods?

3)The PO did some mod with the MAF (maybe the supra one) would this cause me to fail emissions?

4)This is a non Cal emissions truck but the PO also eliminated the EGR would this fail?

5)Should I buy a wideband o2 just to measure the afr with all I have invested, seeing as I don't know what else the PO screwed up?

Thanks guys I appreciate the help.