Two camera system for first wedding

First wedding
Ok so I have a Nikon D810 and a Nikon D7100 I have a Nikor 2.8 24 to 70 and a Nikor 2.8 70 to 200. Im going to shoot my first wedding . I do have other lenses for both but the two lenses seem to be the most dominate in the wedding setting. The issue is obviosley The d7100 is a crop sensor and the the D810 is a full frame. with these two lenses and cameras what would be the preferred set up over the other and why. I do have 35mm dx 1.8 for the crop and a 50 mm 1.8 for the full frame just trying to avoid lens changes but this may be a overrated issue ?
Any input is cool Thanks
Dave