I agree this build up can be common on old engines. I have seen even worse on older motors, I second cleaning it up the best you can. I had a 4.3l (so basically two cylinders chopped off) which was 3x worse than that. Cleaned it up at 130k and drove it 30k more before I sold it.
My 383 Stroker Runs about 180 Water temp and 200-210 Oil temp all day long even when it is over 90 degrees. I am still running stock water pump, with stock radiator, but did bypass radiator to run an external transmission cooler.