The job between Pinconning and Grayling switches Standish but I think Kawkawlin is switched by the Bay City yard job.
Whatever number of engines that are kept in Grayling are serviced in Saginaw.
I know Wiki says the night Grayling job runs to Pinconning and back but I have watched several videos that show a crew taking the train in Pinconning and going to Grayling and back to Pinconning.
PatC created a monster, 'cause nobody wants to see Don Simon no more they want AARR I'm chopped liver, well if you want AARR this is what I'll give ya, bad humor mixed with irrelevant info that'll make you roll your eyes quicker than a ~Z~ banhammer...
393 and 394 use the same engine(s). 304 uses the road power from Bay City, swapping trains at Pinconning. At least that’s how I understand it. So at most you’d have a pair of Geeps in Grayling for 393/394 and the road power for 304 waiting to go back south.