While in a local Halo 3 custom games match you can press the following button combo (While on the default control scheme) LB + RB + Left Stick + D-Pad Up + A (Really awkward to push, I normally hold the controller upside down to get er done) Hit them all at the same time and hold for a few seconds and you'll get this; Exact coordinates for where you are, using this you can have the exact distances between objects / locations when remaking a Halo 3 map. If you do this button combo while playing on the 360 you can switch to forge and it will still be in effect. It still works on the MCC but can only be done in custom games / won't be in effect once you leave the match. Compared to the detailed movement coordinates in Halo 5, you will have to multiply the Halo 3 numbers by 10 for the numbers to work. (Move decimal place one to the right) Hope this helps with some remakes!