I'm getting ready to drop my '99 4R70W transmission's pan to change the filter and drain the torque converter. I'm planning on installing a B&M drain plug, and would really like to drill a 3/16" pilot hole in the pan while it still still has fluid in it to drain it before removal.

Obviously, by drilling it while it is still mounted on the transmission, I have no idea what lies on the other side of the hole. I understand that I need to put some hose over the drill bit to restrict its depth to around 1/4", but I really need to make sure that I have inside clearance for the plug itself after the hole is drilled.

Could someone with a plug already installed please provide me with measurements to their plugs location? For example, along the lines of: "Perfectly centered left to right, with center of plug 2" forward from rear of pan", or something like that. Thanks.