How to make it so that object does not overlap another object in grid

How do you do it so like for example if you want a grid placement system the selectionbox will turn red whenever your object is over that certain part
*Or model or array of models

Okay so I am currently reading EgoMoose’s thread about grid placement systems and he uses the Touching thing to detect overlapping which is a bad idea because you cannot insert touchinsert anymore and the whole touching thing is like defunct because it has alot of bugs and yeah