Mike,
Those are normal numbers for an older engine and both cylinder are pretty close together. Doesn't sound like anything seriously wrong there except normal wear.
I'm clutching at straws here, but the next time you warm up the engine, stop it and feel the face of both rads to see if one is noticeably cooler than the other. The way they are plumbed, you could have one partially blocked and still have good flow.
I'm still leaning toward Nick's idea about having the rads cleaned.
Bill.
