Suburban doors on a truck?

[MONTEZ]

I have an 85 GMC that I am replacing the doors on and I have a cousin who is willing to give me a mint set of front doors from an 88 Suburban. My problem is that I always assumed they were the same. I have been all over he net and can't find anything to confirm or debunk this. A guy I work with says they won't work, that they are longer and have different hinges. The worst part is that I called my go to guy (been to body work for 40 years) and he even said he has never tried it. I looked at part numbers on other sites and can find distinction that it would be different. Can anyone help me out before I drive an hour to go pick them up and try to install them to find they in fact don't fit?