I got looking at the picture with the red box representing the core and started thinking if the pins where not 45'ed then the pins would cover more area of the heat output from the die.....
Also by making the pins normally square milling will be considerably easier. Now all I have to do is strait passes with a 1/8" endmill.

Will make using the roughing endmill so much easier aswell as I can use the hand wheels for that and go much slower. In fact this entire block could be made with hand wheels! Not that it will be though. If the performance is good then it will be a good example of an easy block to make on a manual mill.
KingPin eh??? Hummm...