Was hoping you can perhaps provide an update to this thread for those who might be considering mirroring your efforts.
All this effort is no longer necessary. Just buy GBTC in your brokerage IRA, or maybe COIN next month, if we are lucky.
GBTC hasn't been following the BTC price very closely lately. For example, I bought some GBTC six weeks ago when BTC was priced around $900, and the value of my GBTC holdings are *down* 2.25% (and were down more than that a few weeks ago). Given that GBTC shares can be redeemed for actual BTC, I doubt the GBTC price premium will ever go into the negative significantly, but you can get caught in a situation where a significant premium can be absorbed in a sell-off before seeing any gains, depending on when you buy in.