48 Degree R3 Block Using 59 Degree Heads?

Pipe Dreams said

You can use a 48 degree head on 59 degree block, but not a 59 deree head on a 48 degree block. All R3 blocks are not siamese bore. You can get an R3 block 48 0r 59 degree with or without siamese bore.
My 340 resto block is is a 59 degree non siamese R3 block with the extra head bolts milled off. If you decide to go with the 340 resto, comp cams is the only one I know offering an roller lifter fits in this block and I have not heard good reviews of them.

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The big issue I see would be lobe placement with the different lifter bore centerline. You would need a 48 degree cam core with a 48 degree block , which is not exactly inexpensive. Then I don't know that the heat treat on most blanks or ground shafts that you might re-grind will allow for anything but what can best be described as a serious profile.
Can it be done ? Yes.
Should it be done ? Unless you are doing a real balls out effort ( in which case , you would probably want 48 degree everything ) , I like the resto block approach.
If you are anticipating more than 600 h.p. , then you certainly want to consider more than a production casting.
If you will be closer to 500 , a stock block might be an attractive alternative. If you have to prep a stock block , it isn't cheap......but prepping an R block isn't either. Stock block would be cheaper , R or resto would be stronger.
Add up what each would cost with machine work , factor in potential re-sale and the decision makes itself for me.