Mark, your going to get mixed opinions on this. If it's a Fox hemi kit, the stuffer backplate is a must. Reason being is that it's a machined backplate and not a casting. This means, the gasket seals better and the ears aren't being subjected to bending like the cast version. This doesn't mean that it won't bend, you just snug these down. I prefer Fel-Pro gasket material over the cork but that's my preference. The main importance is the fact that the rod doesn't always stay properly on the crank pin. The stuffer back plate is hard anodized in the event of a rub and it protrudes more into the case over the stock version assisting the rod.
Some will say the hemi adds more power, I don't buy that statement. In fact it lowers the already low compression engine even further. I personally wouldn't use any head gaskets if you choose to use the hemi head, just lap the top of the steel liner. The head was never fully finished when Marvin Denny designed it and he would finish it for you if you sent it to him. It makes the engine harder to start and I have done extensive back to back tests using the stock, Fox hemi, L&J head and found the stock to always work better. The stuffer backplate does seem to boost performance. Nothing indexes the button so you must be careful that the baffle of the piston doesn't strike the head. There's very little clearance.
The problem with the Fox is that the crank can develop a lot of run out in the shaft bearing. Not always a bad thing with a old engine because a worn one runs the best. However, seeing you have a new 60th, that would be the engine I would put it on. The other problem is this, the Fox case is like a eggshell, the older ones are even worse. If you tighten one screw incorrectly, you will dial a bind into the liner that could really FUBAR your engine if ran. I would leave the old engines as is and not compromise the carbon/castor goo that's sealing the head.