Speaking about 6143 current model has some differences compared to BI mesh as seen on https://postimg.cc/N5H2dvsV where the left part is the 3941 model, middle part is the 6143 both from LDraw while the right part is 6143 from BI meshes.
LDraw version of 6143 prevent to fully insert middle ring of 78258 as seen and discussed on BL forum: https://forum.bricklink.com/viewtopic.php?t=13663
LDraw version of 6143 prevent to fully insert middle ring of 78258 as seen and discussed on BL forum: https://forum.bricklink.com/viewtopic.php?t=13663