I just had someone read the trouble codes on my 94 C280 because the check engine light came on. Codes indicate I have a clogged EGR tube. I understand there are two tubes on this car. Can anyone tell me if they can be cleaned or will I have to replace them? How can I reset the check engine light?

You have a 104 motor. Try a search for EGR Tube or 104 EGR tube. There is a tube that goes from the EGR valve around to the intake side that commonly gets clogged up. It can be cleaned but there is a new style tube that is less prone to get clogged. But you'll get a lot from a search, including how tough it is to get to it.

For clearing the code - what sort of diagnostic plug do you have? A 104 motor would normally be a 16 pin but it seems to me your car was partially OBDII compliant.

Don't assume clogged tube, even though it is a common egr code problem...

A simple flow test is to apply hand vac to the egr vac port while engine is at idle.. if engine goes lean and attemps to stall/runs rough, the tube is not blocked .
There is a SOV valve that can be at fault and an even more common fault on 104 is the vac line going to the SOV...they crack from heat b/c they are plastic..replace w/rubber. Plus , the egrs on eatrly 104s were known for sticking...there has been a part change..
So, as you can see, an EGR code is not a Tube code, it is a system failure code and requires testing the system...