I have a 290T chassis out of a Philharmonic, and I own a Garrard AT6. I don't have the rest of the bits, but I can tell you a bit about the components.
The 290T is a pretty decent receiver. Its FM stereo, and the tuner works very well. The troubles with it are the output tubes and the lack of a magnetic phono stage. The output tubes are ELL80 tubes, which sound good but are quite pricey to replace if they wear out. The last used set I picked up ran me 50 bucks, and that was a reasonable price. They're also not a powerhouse, good for about 12 watts per channel. The lack of a mag phono stage means you'll either be adding one in if you want to upgrade the AT6, or dealing with a ceramic cartridge. The AT6 itself isn't bad, but its not that special either. I have one and stuck it in a console to upgrade from an even worse machine. Its an easy refurb, but mine did need a $30 idler wheel. An AT60 or an SL65 would be a slight upgrade but would retain the same chassis and overall look.
My very honest suggestion would be to aim a little higher in the Fisher chain if you can. Even if its not something with an 800 reciever, something with a mag phono stage and tubes that aren't an arm and a leg would be a good thing. If you're really set on one of these, maybe consider not selling off your other gear to get it. It would most likely be a sonic downgrade from what you have now.