I love plane workshops! I know what you mean about not seeing it all in a day though. Its a rather boring long drive for me to be tempted to go back within a short time period to see the rest....I long for the good old days when my friend and I use to fly there in his plane....the best way to arrive!!
The nice thing about the Heritage Motor Museum is that the ticket stays valid for further visits. I've got one from March which will still let me in !