In July the C-19's are in charge every day of the week. The Goose is normally run Monday through Thursday during the off season months but not during July. She should be parked by the enginehouse and you can get photos from the train.
Seeing and riding the train is an expensive proposition, because you have to pay for full admission to the park just to get to the railroad. Current price is $67 but you can get a $40 ticket on line - $37 if you're a "senior." Not that the other attractions aren't worth the price of admission. The Ghost Town is made up of authentic old western buildings with lots of fun attractions, give yourself some time to roam. The coasters they can keep, IMHO.
The ride is free once you're inside the park. The run is a little over 3/4 mile and is taken slow. The rest of the park has really encroached upon the railroad vs. how it was in the 1960's when it circled the open parking lot, but listening to a C-19 work is worth the price of admission for my buck. RGS 41 is the current star.
Check with the planners of the Garden Ry convention and see if they are going to do any special Knotts trips. Often these are one of the "layout tours" with early morning runs before the park opens, cab rides and access to parlor car and business car. These are lots of fun!
I hope you have a good trip.