More info on my own question.
If you face south and look at a point in the sky on the equator, the celestial coordinate system is defined as north “up” (0 degrees); south “down” (180 degrees); east “left” (90 degrees) and west “right” (270 degrees). This is 0 to 360 degrees moving in a counter clockwise direction. A magnetic compass is 0 to 360 degrees moving in a clockwise direction.
Looking at the plate solve info from PinPoint:
WCS: Roll = 88.01 HScale = -0.549 VScale = -0.549
PA = 271.990°
PinPoint (and Astrometry.net) are reporting the orientation of the frame as rotated 272 degrees from north. The World Coordinate System is reporting the frame is rotated 88 degrees from north. PlateSolve2 also reports the frame as rotated 88 degrees. So we have a mix of position angles being reported as CCW from north or CW from north without an indication of which it is. At this point one assumes there is a standard.
While 88 degrees CW is the “same” position as 272 CCW, the 272 degree rotation is up-side-down compared to the 88 degree rotation. Perhaps this is the intent – since APOs, SCTs and similar OTAs invert the image, reporting a frame as rotated by 272 degrees makes it match the non inverted image as would be shown by a product like TheSky6 and other planetarium packages.
The bottom line is that mixing PinPoint / Astrometry.net with PlateSolve2 / WCS will produce conflicting results unless SGP understands that and reports PlateSolve2 position angles converted to conform with PinPoint and Astrometry.net.
The other question is what goes into the FITS header? I would have thought it would be the WCS value but it looks like my SGP images are getting the PinPoint value.