Yeah you can remove the EGR. You'll have 2 holes to plug with threaded bolts or plugs. I don't recall the thread size, but I found what I needed at NAPA when I brought the pipe and the valve in to compare.
The thing under the CC is the Anti Run-on Valve. One of the missing hoses from the Banjo fitting used to go there.
Be careful with the electrical leads, when you remove them. One is "hot" whenever the ignition key is in the "ON" position. The other wire gets it's ground at the oil pressure sensor switch on the dizzy side of the block.
Just keep the hot wire in mind and don't let it touch ground while you're taping it off.
As far as what you can remove, well you'll need to keep the Valve cover vented to the carbs and you'll need to keep the nipples on the left side of the carbs that point towards the cockpit (the ones closest to the air filter's) open to the atmosphere or leave then connected to the Carbon Can by a hose.
Then there's the vent line from the gas tank that is supposed to go to the CC.
If you choose to remove the CC you can 1) leave it open to the atmosphere or 2) (my choice) stick the hose from the gas tank into the hose from the carbs/valve cover that used to go to the CC.
As for the air pump, diverter/relief valve and exhaust manifold air lines, I'd better let a 75-76 owner who's removed all that describe how they did it.
Here's a picture of how I dealt with the emission stuff that's common to both my 74 and the 75-76 engines.