I am using this mod in my HSFX 5.0.1 install. I'm liking what I see except for the 3D issues on my P-38J and P-38L stock versions (see screenshot). Look at the engine cowlings. They have become 'unattached' from the main body.
*I'm using your HSFX version from the Mediafire link provided by KeyGirl.
**EDIT: I deleted the Engine1_D0.msh and Engine2_D0.msh files from these P-38 folders and that seemed to resolve the issue. However, I still see some issues with two left-engine spinners and some seperated 'seams' in the booms on some P-38 models. This all seems to be related somehow to HSFX, as I don't see any of these 3D issues in UP3. (I know that the spinners in HSFX have been 'rounded' while the ones in UP3 have not, so maybe that could be where the solution can be found.)
Even when I completely remove this mod, I see some 3D issues on several P-38 models where certain areas (mostly the engine/spinner area) do not 'fit' correctly. There are spaces/gaps or general misalignment on some models while others seem ok. In UP3 I don't see any of these issues at all. Again, this seems to point to something in HSFX.

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