That is something that stood out along with so much regarding the "new" design BMP aluminum block. 4.50" stroke w/out clearancing. I haven't discussed an external pump, but with a 4.25" stroke, I wouldn't expect to need or want one, besides, the Wraptor serpentine belt, pulleys, and accessories system may make adding any additional belt driven anythings to it..."challenging", especially for me. The work you're doing OTOH is outstanding and maybe you could come up with something if you had to.