2000 GMC Antifreeze in oil.

I have a 2000 GMC C 2500 4X2 with a 5.7 Vortec. It has 211,000 miles. I checked the oil in in lastnight and it was 4 inches over full and looked like it was muddy. I checked the radiator and it was about 4 inches low. I changed the oil and checked the compression and got got exactly 125 psi on all cylinders but one and it had 127. It got antifreeze in the oil just from turning it over to check the compression. Any one got any ideas where the antifreeze is coming from. Intake, head gasket, cracked oil cooler in radiator?? Thanks

Intake, Head gasket, cracked head or block!
1) Drain both the mud & OIL from engine block ASAP.
2) Drain coolant.
3) Put 3-quarts of cheap oil in block.
4) Turn engine over a few times, and drain oil.

How did the drained oil look?
Was there coolant freeze protection in your coolant system?

The Age, mileage, and GM dexcool might played a part in the intake manifold gasket going bad.

I did drain the oil and it came out clumpy and very thick. It actually had the green coolant in it that came out right before the oil.

Need to perform a smoke test on the Intake to check for leaks.
5) Remove the Air filter, and wrap filter in glad wrap.
6) Put Air filter back in.
The idea is to block all air going to the Intake.
7) Remove the Brake booster vacuum hose from the brake booster.
8) Light a Black & Mild cigar.
9) Blow smoke into the brake booster vacuum hose and plug with your thumb.
10) Repeat smoking, and watch for smoke leaks.

Sorry it took so long. I have been busy. It ended up being the intake gasket.

Sorry it took so long. I have been busy. It ended up being the intake gasket.
the head wasn't crack at all?

The heads were ok. Replaced head gaskets while I was in there.