I'm working on a map that I imported to Pro from an MXD. The map inlcudes layers that are symbolized using Unique Values but class are composed of groups of unique values separated by semicolons (see below). I want to combine two of these groups by adding the two ramp values to the streets class, but I can't figure out how to edit the Value field.

Does anyone know how to group values or to edit groups of values? I'd rather not make a whole new class and then delete these two because the list of values in the Streets class is very long and it also won't let me copy the value to paste it into a new class.
Any tips are appreciated?