Have only just seen your post, I'm actually off to GDSF this afternoon, however there should be a number of items which will interest you across all areas of the show. There are usually a couple of steam engines with WW1 backgrounds and there has sometimes been something in the military and commercial sections, whilst the motorcycle tent will also be of interest.
To be honest you never really know what is going to turn up at the show until you are in attendance, I'm sure you will enjoy it like we do every year!