1 remove egr cooler,...just weld it up and knock the scoop out or a IPR gen2 kit?
3 How can i test if my HG are not leaking and be sure it is a leaking egr only?
First you need to find what is causing the loss of fluid. Since your temperatures are fine, I doubt your Degas cap is bad, but you will need it to operate correctly (18 PSI) for the head-gasket check. Hook up a T-fitting to one of the hoses on the Degas bottle and run a pressure gauge to a location you can see while you are driving. If your HGs are bad, as you increase driving load (put your foot down), the PSI will increase above 15 PSI. There is a sticky for the HG items needed.
Most EGR cooler failures come after a oil cooler failure, not before. However, it can happen. For the EGR cooler failure, you would see white smoke/steam out the tail pipe. To confirm this, park nose-low and remove the EGR valve. Inspect intake manifold for moisture. If you are still not sure, remove EGR cooler and inspect/pressure test. I don't have it, but I really like the IPR Gen 2 delete. I cut my scoop out and welded it smooth, but a simple plug for the V-band clamp would work (if you were keeping it to install a new cooler at some point).
2 i think my delta,s are fine should i need a new oil cooler while i am in there?
If your delta is fine, there is no reason to replace it.
There are parts like Updated Hpop fitting - turbo downpipe - and all kind of o-rings and gaskets that i might need.
Don't go replacing things unless there are problems, or you are at very high miles/kilometers. The regular exhaust and down-pipe are OK for moderate HP modifications.
Not too many trucks like yours in the Netherlands, nor X-stars either!