Are most single DIN cd players' mounting sleeves the same? In otherwords, would a mounting sleeve/can/cage from a Sony deck fit a Pioneer deck and vise versa? Or are that many differences between the two. Most of them look the same between brands from what I can see. I know that the single DIN Pioneer AVIC's use a different cage than the regular HU. Thanks in advance.

 

No, they're all different. The clips on the side that hold the deck in place are not interchangeable, and your stereo will fall into your dash when you slam on the brakes.

 

Size wise they are all the same, but as mentioned the way the HU "locks" into the cage will differ from one brand to another even from one model to another, however there is always a mod the can be made so you can get a HU to "lock" into another brands cage.
With most Honda/Acura a properly installed back support on the HU is all that is needed to keep the HU in the cage. 94