Well, there are probably quite a few pieces of repairable equipment there but remember that alot of the cars in Beech Grove are damaged beyond repair. A substantial number of Superliners were involved in very serious incidents and never can be used again because they are either way beyond repair or the cost of fixing them is way too high to justify doing it.
As for enough equipment to Make the Cardinal and Sunset daily at Beech Grove, well if every piece of equipment was put back on the rails yeah I bet there would be enough. But I think those trains are low priority cases. The long distance equipment situation is stretched very thin as it is now and the cars getting released from Beech Grove would be better off being used to release the strain of the fleet and offer increased capacity on the main long-distance trains.
St. Paul, Milwaukee, Chicago (TCMC) second daily service