I got another question for the community regarding a shotgun purchase. I have recently bought a Remington 870 SPS Super Mag to replace a old Winchester and I would like to replace the trigger housing assembly with a metal one. I decided to buy one online and nothing on the page suggests the super mag is different. It wasn't until after I received it that I read the super mag might not fit but nothing concrete.

Dropping the trigger housing into my 870 fits fine. It passes the function tests and everything. My question is are all remington 870 housing interchange? And if not, what danger would it pose, if anything? Also would it give any indication of not fitting?

I'm not sure what help this will be but until someone with more info posts.........
The standard 870 trigger guards  all have totally different factory part numbers then the Super Mag models.

The "aluminum" 870 trigger guard unit is made of compressed, powdered aluminum, not an aluminum forging or even casting.
They aren't nearly as strong as thought.
The plastic guard has the advantages of no finish to wear off, if it's bumped or struck the guard flexes and returns to shape while the aluminum just breaks, and the plastic is self lubricating,
In actual use the plastic stands up every bit as well as the aluminum.

With that said the cops and I too just prefer the aluminum...just because.

I would NOT buy a standard 870 trigger guard and hope it will work in a Super mag unless someone says it will work.

I was originally under the impression that the only parts different on the Super Mag were the receiver, bolt, and the barrel's chamber length...but as dfariswheel mentioned the part numbers are different for the trigger groups too so maybe there is something different (maybe a stronger Carrier Dog Follower Spring ? )

Since you already have the tripper group in hand give it a function test and report back to us (be sure to test it with both 2.75” and 3.5” shell, that may tell the tale)

Hey thanks for checking up on it. I did take it to the range over the weekend and tested 2 3/4 and 3 in shells (didn't want to try the 3.5 since I never would use it). And it works... just fine as far as I can tell. I honestly can't see any difference between the metal and the super mag one.

I did email Remington customer service and they told me they can't help me:

"We don't recommend deviating from the original factory specifications. Unfortunately, we are unable to assist you with special orders on our products. Thank you for your interest and have a great day. "

Is what they told me. So I have no idea now but it works and as far as thinking about it logically I can't really understand why it would break it.