Mosfet transistor identification help needed

I have these 2 faulty mosfet power transistors they I’m trying to find an identical match for but am not very knowledgeable in component matching. I’ve bought what I thought was a straight swap that matched the number/letter scheme on the top line IRFP460 with only the second line not matching up but I now keep blowing fuses on my system. Could anyone help with what is a direct replacement or what do the Y58K BQ numbers/letters mean on the line below as I am not able to match these with a new component.


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Ok so some more information. It looks like I have 420v coming from a capacitor which goes to the middle leg of the transducer which by the looks of things is meant to do. So withought the meter heat sink I get no fuse blown but I can detect the 420v on the back of the transducer. On the heat sink I notice there is a very thin plastic film than separates the heat sink from the transducer. But the screw that holds the transducer to the sink was touching the transducer thus allowing the 420v to go through to the other transducer thus shorting and blowing the fuse. I still think it’s a bit strange that it’s only a small film to separate them. So not sure if the voltage is ment to move through the heat sink but I would not have thought so as this would make the heat sink always put out 420vdc. Do you think I should just try it back in my device with the sink removed as a trial then if all good reinsulate the transducers from the sink and reinstall? Sorry for the confusing story 🤪