Touring plan with attraction set at a certain time

Is there a way to pin an attraction at a certain time? We’d like to do Splash Mountain first then have everything optimize from there. If we leave it out it says to do Space Mountain first, which is on the other side of the park. If we leave it in, it won’t stay first. Any help would be appreciated!

One way is to optimize, then manually move Splash to the top, then evaluate. Optimize will always rearrange the plan. Evaluate will maintain the order but update the times.

You could add it as a fixed time break from 9 am -? At a nearby location .