As I said Sunday, I am sure the oil cooler has gone (unless previous owner had recently changed but not had time to do more flushes?)
I think there is too much there for that, I remember after yours was done, there was oil in there, but specs, not half a oil tanker!
Oh the first couple of flushes there was lots of oil. Double check with previous owner 
Err I did, he never touched it. 
Ah... ...OK, defo needs doing. But you've helped do one before, so you'll have no probs - take your time, don't rush, and give it plenty of time to seal. If stat is weeping, reseal that as well. Remove all rubber coolant pipes and flush them through thoroughly. Same with rad. Same with waterpump and block. Possible you may have to replace waterpump seal, but I would try to delay that until changing cambelt and waterpump (ie after a few good flushes)
My top tips, from bitter experience...
1) Do NOT bend the oil pipes!
2) Do NOT shear the banjo bolts
