@Rizvi79: Wow indeed! That looks like a nice clean project you have going there. If I am not mistaken thats a full 70series/Bundero/Prado suspension and diffs that you have neatly pasted onto the 40s frame. A pretty good set-up indeed....
To be honest coil spring suspensions are something that I don't really understand very well myself though I am aware that these conversions have been successfully happening out here for the past 7 / 8 years now. Personally I have never been able to hitch a ride on one of them converted rigs, and I only have things I have briefly seen or overheard to go by. There are many others PW 4x4 heads out here who are more experienced and qualified to speak on this.
I do feel that the most important things at this stage is to get the upper frame/coil-spring mounts levelled correctly so as to ensure the rig is perfectly balanced when standing still. It took a while to get this done right on the very early such project : Imran mechanics own green CJ7 Wrangler with same diffs and susp (pics somewhere on IJC and PW forums). He had Mr. Moon, one of the best frame guys around here working on it and getting his ar** kicked around for a few weeks before it all came together right. But then again, that was a long time back and some of the frame guys are much more experienced nowadays.... It seems that your in good hands though!
There are some other finer points here that come to mind but I feel that if you have this one down then the rest is something you can fine tune to a certain extent once you have things rolling. And there are always certain things that you'll have to live with one way or the other in such projects, as even manufacturers don't always get everything perfect all the time when it comes to suspensions... but then again life is a game of choices and compromises, isn't it!
All the best with this one, do keep us posted!