Setting the right coordinate system

Hello,

I have a question about projection. I have an arcgis project and all my shapes are in:
Geographic Coordinate System: GCS_North_American_1983_CSRS
Datum: D_North_American_1983_CSRS
Prime Meridian: Greenwich
Angular Unit: Degree

Projected Coordinate System: NAD_1983_CSRS_New_Brunswick_Stereographic
Projection: Double_Stereographic

In the end I will use the project in a simulation system VRforces. The VRForces manual states that if I have a large terrain larger than a UTM zone a geocentric projection is recommended. The terrain I use is larger than a UTM zone so I want the right projection.

Because we use wgs84 on our maps I was thinking to use that. I am new to this but is this the right choice?

2nd question is the how. After same reading and experiencing I used the project tool in arcgis 10.2
Attachment 30064

I found out the when I use arcCatalog and in the properties windows and the xy coordinate tab I set the coordinate system it’s a lot less work. But I do not have to set a geographic transformation. What is the best, accurate way to set the coordinate system.

Thank you, Greetings Peter

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