Engine Perch Mounting Hole Question

[Pontitruck]

Hi guys,

I am in the middle of adding a 4l60e to 5.3 in my 65. I have the DD Slider set up but I believe the perches need to be move on the frame to the forward location as the trans is tight at the floor and I have quite a bit of room between the electric fans and the pulleys. You can see I'm adjusted as far forward as the sliders will go.
My question is what holes are your perches in, front or back for an LS? The pics show the holes closest to the front.

Thanks