'92 K1500 350 TBI stumbles and recovers while braking / slowing down when warm

Hey all just bought a '92 GMC K1500 with the 350 engine for the heck of it. Been fixing up a few things on it, and it runs just about perfect except for one minor thing. When its up to normal operation temperature, the engine sometimes acts like its going to die when I come to a stop at a stop light or slow down to park. The RPM's get real low and it acts like its going to stall out but it recovers real quick and then acts fine. Hasn't died on me yet. It feels like a fuel starvation issue, or could possibly even be too much fuel. Only lasts a second or two and doesn't give me any problems after that. Doesn't seem to happen when the engine is cold. Truck has good power and drives fine. I replaced the fuel filter (which was kinda plugged up), didn't really change the situation. It has been suggested to me to replace the fuel pressure regulator diaphragm in the throttle body. The only other thing I could think it might be besides that is the fuel pump, but it just doesn't seem like that would be the issue considering it runs great in all other conditions. Truck starts up and idles great. All tune up items have been recently done. The other thought I had would be maybe something to do with the EGR system? Any thoughts? Thanks!

So to clarify, it stumbles and almost dies when you step on the brake pedal? Or will it stumble and die when you let off the gas.

If it only acts up when you use the brakes, I would suspect a problem with the vacuum booster, it could have a leak that only shows up when you have your foot on the brake.

It stumbles when I let off the gas, not just when the brake pedal is depressed. But, I THINK the problem may be fixed. There was a vacuum port blocked off on the EGR solenoid. It was simply a vacuum hose with a screw in it and looked like it was added so I took it off for kicks and giggles and I haven't been noticing the problem anymore. Still I wonder if the EGR system may be a little clogged up or something due to age. Will take it to work today and see if the problem comes back.