I want to store my bitcoin offline, and I want to engrave my 256 bit number (master private key) on metal, and not ever have to use 24 words. know this is riskier (if I record one of the numbers wrong I couldn't recover my bitcoin), but I'm not worried about that and I want to go ahead with my plan.  How do I do this? I tried electrum but it looks like the only way I can use electrum is with seed words, which I refuse to use.  Any help or pointing in the right direction would be greatly appreciated,  I've been trying to figure this out for a long time.