FSX:SE MD-11 Stabiliser trim units versus pitch on PFD?

[HighBypass 2,339]

When the aircraft is cruising straight and level the PFD indicates a pitch angle of about 3 degrees or so, especially when zipping along at M0.84 at 30000 feet (just under the red zone on the ASI): She'll not get much more nose level I think!

So far so good: I believe that between 2 and 5 degrees is a normal pitch attitude for level flight in the real world.. HOWEVER, and this is where I am puzzled...

When I check the stab trim indicator it's showing just over 6 degrees ANU (aircraft nose up). This is with the C of G at about 26% (any more and it triggers the c of g limit warning). Despite me altering the amount of payload in the forward and aft sections (FSX fuel & payload menu), the stab trim always seems to return to the same value. It seems quite high given that I'm deliberately setting up an aft c of g condition. If I had a forward c of g position I could understand the stabiliser having to adopt such an angle to keep me in the air, if I'm understanding real world conditions correctly?

I'm sure I've seen real world videos on youtube where the stab trim number is much lower at a similar c of g position...

Any experienced PMDG users (close to as real as it gets) or indeed real MD-11 pilots (actually as real as it gets!) care to join in? Thanks.