[Captainfab]

Yes you will have to convert to side mount engine mounts. From a quick test fit, the '67-'72 small block rnginr mount brackets seem to fit rather well. Some say a ~1/4" spacer is needed on top of the frame. If this were my truck, I would modify a set of '73-'87 engine mount brackets to fit the early frame. Those engine mounts are a much better design. The original bellhousing crossmember will need to be left out and a trans crossmember fabricated.