Jack,
Certainly worthwhile spending some time in the museum.
If you get a chance, I recommend you also drive past the old Islington Railway workshops before they get taken over completely by retail development. 
I presume that's where your late dad worked. 
The main brick buildings still stand and are being preserved by the National Trust, but they'll soon be surrounded by "big box" retailers.
This video gives a great potted history of the Workshops....
SA Life - Islington Railway Workshops
Alan