Splitting Mold of complex organic shaped object

I have the split of an object that I would like to cast. And I have a split of the mold.

I would like to connect the edge curve of the open mesh of the model to the edge curve of the open meh of the mold half.

Mould-Split.gh (1.7 MB)

Any help would be highly appreciated!

Thank you, Peter

The ! _RibbonOffset command could help in those situations. However, you will have to create an extended ribbon offset surface and a higher box than the current one, because the former will try to extend sideways. Both models must be long enough so that they intersect together. Then you simply split them and delete the excess pieces.