If Output port 2 goes to Input port1, then you have a conflict due to the dimensions. Including a signal specification will not solve the problem. In this case, you need to select which 468 of the 702 elements from Output port 1 should go to Input port 2. For this this you can use a Selector block, found in Signal Routing library (here, Input port size is 702, and then in Index you define the elements. For example, the first 468 elements would be [1:468]).
Hope it helps!
