Keep its under 1200 honestly. 1000 doesnt work for everyone exspecially like myself running 190's etc. 1200 has always been the boarder line for EGT's. 1700 ??? how did you manage that ? Ive never seen anything that high even with my mods.
How are you keeping your trans at 160 you have no control on that, guess being that far north the weather keeps your trans cooler. Im normally in the 160 to 180 temp range you really have to worry about your trans when you start to see 210 constant.
Now I cant remember exactly but oil temp and coolant should only be 15 degrees apart. I believe the normal operating temps if the EOT exceeds 15 degress of the coolant then the cooler is failing or has failed. EOT 200-220, ECT 195-210 max.