DIY ACA mini

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ACA Mini Harris 100Hz.pngACA Mini Vishay 100Hz.png
 
Finally getting around to getting parts for my Almost Clone board (Thanks Kevin and Mark!). DIY Audio Store has some Harris Mosfets in their F-4/BA-3 kit. They are Harris IRFP9141 (and I assume the complementary IRFP141). Perhaps overkill, but the store matches them, so it seems like a preferable source to Rochester and their burdensome minimum order. My question for the experts here is this a viable alternative to the IRF9520/520 semis in the original kits? Yes they're TO247 vs TO220 so I'd have to trim/squeeze the legs to get them to fit the board. Anything else I'm missing?