Can I use a 1969 LTD as a parts car?

I am just learning the ins and outs of remodeling and cars in general, so sorry if this is a totally insane question.

I have a 1969 Mustang Fastback and have access to a 1969 Ford LTD. They are both 390s. I was wondering how they compare, spec wise, if at all. Can I exchange rear ends, use brake lines, calipers, etc. I guess I would have a spare engine as well.

If anyone knows of a website where I could put the two side by side and get measurements, please let me know.

Thank you.