Tarfu43

My A1 overheats (goes past 200 degrees) and boils-over within 10 minutes of idling. I've changed the thermostat - no help. I haven't checked the timing or carb adjustment, but the jeep starts and runs great, so I don't know how it could be a timing or carb issue. Looking in the radiator fill neck, there seems to be a lot of crud in there, so I suspect the radiator is clogged. Does that sound right to you guys? Is there a way to confirm the radiator is clogged before I start taking things apart? The TM states to clean the cooling system per TM 9-2858. What's involved with that? Should I just take the radiator to a shop and have them look at it? The first time the radiator overheated, I wasn't paying attention and the oil pressure dropped to 10 psi. Should I change the oil as a precaution?
Any help with this matter would be greatly appreciated. I'm at a standstill until I can figure this out. Thanks!