Mine is a Model 400, and I think yours is too. It's a great tool. I bought mine new, but can't remember how long ago (a senior moment ). Instead of plywood, mine had termite barf (particle board) tops. One night, I left it out in the rain.
I am now more than happy that I did, as I replaced the tops with 8/4 hard maple, and added a lot of dog holes in more logical places. I often use it when I'm working or demonstrating away from the shop. Here it is with my bench-on-bench mounted.
Since that picture was taken, I have replaced the masonite lower shelf with some tongue and groove bamboo.
I also sometimes configure it with a mini-lathe, blast shield and work light.