[Eliot Ness]

The tubes in the back say Philco on them so I don't know if its possible to switch the chassis....(the part with the tubes on it?) and the cabinet..(the main part of my radio?) that's why I'm not sure its a true Slivertone.

The chassis tag has a faint 1720 stamped on it, so it is definitely a true Silvertone.  Well, as true a Silvertone as it can be.  Like everything Sears sells they contract out to other manufacturers to make items with the Sears name on them.  In the case of your radio it was actually made by Colonial for Sears.  Colonial made a lot of radio back in the day for them.

As for the Philco tubes, it was not uncommon to have tubes replaced by a service shop, and they would use whatever brand tubes they had on hand.  In this case, the tubes are branded Philco. 

If you go to Kutztown in the middle of the main pavilion will be the DVHRC (Delaware Valley Historic Radio Club) booth.  They often have a fellow doing free repairs for folks so he would be glad to look at it for you.  Or stop by our booth (#312) in the main pavilion and we'll look at it for you.

Good luck!