Roger is correct. Any differences will be minor and you will be able to deal with them. For instance, somewhere between 1984 and 1987 Airstream switched from individual block capital letters in the logo to script. Not a big deal. Interestingly, the Excella letters changed from script to block letters.
There is an Owner's manual for 1987 available but. like I said, I rarely look at mine (it's a 1983 for me). I'm not even sure where it is. The main thing I remember from it is how good huge plaid pattern bell-bottoms really looked on men (not very).