Could there be a structural problem if I put a 289 in a 66 Mustang manufactured with a 6 cylinder engine?

Mustang, all original matching #s 6 cyl engine currently under restoration considering a 289. worried that there was more than one platform for that make and additional power could damage the car? Am I crazy? how do you know you're right? I am not doing the work, I am not experienced, laymens terms will be appreciated. I have heard both yes it could damage. and, No way it could. I don't know who is right.