What are the disadvantages of having a baitcasting reel on a spinning rod? Why should you not mix the two or is there no significant difference?  Any info. would greatly be appreciated.

The rods are built different for each application.

You wouldn't put a truck tire on a car (or maybe you would if you're from the deeeep south,lol) even though they are both tires.

Each style has different reel seats, grips, and eyes.  The line comes off the reel differently, hence the much larger eyes on a spinning rod.

I had to use one just like that, once on a guided trip in Cancun. It was the only baitcaster the guy had; an old green Curado mounted on a BPS Bionic Blade spinning rod.

Makes one realize the importance of the trigger on a baitcasting rod's reel seat.

I would not recommend it.

Since the first guide is so far away from the rod it won't cast as well, and will increase backlashes.  It will also make the rod want to twist.  And since the spine of the rod will be on the wrong side, the action won't be anything like it's designed to be.

Thanks for all the information on the subject guys