You have to decide whether you are going to skim bed, or conventionally bed the action.
Skim bedding fills low spots, but largely relies upon contact with the original material - think about leading a hotrod - we fill everything with body putty, then sand down so the majority of the surface is the original metal, ONLY leaving filler in the low spots. In this case, the epoxy bed doesn’t have any structural integrity of its own, but rather it is only filling in small microvoids between the original material and the action.
Alternatively, conventional bedding will ask for a thick bed of epoxy, to ensure the epoxy bed itself has substantial structural integrity. It’s pretty easy to bend or break super thin epoxy wafers, so we want to add enough that it doesn’t want to readily flex. I typically don’t hog out 1/4”, but I do set a depth gauge on a drill bit (or router) in most of the action inlet and sink 1/8” guide holes, and after inletting, these are wiped fully by the rest of the cut, and typically slightly over cut, so I’d be somewhere greater than 1/8”.
In theory, skim bedding produces less shrink than conventional bedding, which SHOULD yield a tighter fit to the action, but it then fully relies upon the hair thin bedding holding strong.
Bedding jobs aren’t forever either. A guy can need to refresh a bedding job every so often, whether completely redoing the job or skim bedding again on top of the original bed.