trim routers

Hi,

I set up my Z for use with a el-cheapo trim router, one from Harbor
Freight.

Now I want to move up to a more substantial unit, but it seems the HF
unit has a straght round cylendrical body, but the Porter-Cable and
DeWalts are odd shape plastic bodies. no meat to clamp onto.

Does anybody know if there is some sort of trim routers with a round
metal body that can be used to hold it ?

The larger units have 3-3/4 bodies, but that is way too big.

Dave