I did just this a few years ago on a Wildcat stock.
You will have to move the front guard screw rearward about 1/4" and mill a new slot for the recoil lug.
After it's all bedded and finished you can't tell.
Bedding the clover leaf tang should not be a big deal.....Stuart at Wildcat stocks did the bedding..:-)
There might be some work required on the rear of the trigger guard also.
Some stock patterns don't mesh well with the Pre'64 metal in this area.
"greydog" who's a member here is the guy who knows all there is to know, (and then some) about your question.
Rembo, I think you got your wires crossed here. Pre-64's, whether pre-war or post was had the same footprint. The only issue is the rear tang, it would need a bunch of fill and then paint or some type of finish. I think you may have mistook a pre vs. post 64.
