A couple contrarian thoughts:
Right now you can make over 5% in 1 month treasuries. No rush to buy anything.
You might want to use that money so you can make max 401k or IRA contributions for a period of years. There might be major tax advantages therevthat easily justify spreading the purchases out over years. Dollar cost average into a brokerage account as well.
I see a few problems with new blindy buying SPY.
Historically, there was a lot less passive money that went into these companies simply for being in the index.
You might have a company with garbage financials, or that is engaged in fraud but so long as it is in the index you'll be automatically buying it.
The Ukrainian war showed us that they are willing to manipulate the content of indexes for political reasons, separate from the stated purpose of an index. When you own an index fund, someone can cause a fire-sale of your investment in company x just by dropping it from the index.
You also have the potential issue of the fund taking your shares and voting them against your interest in pursuit of whatever goals they may have, net zero or whatever.
I would consider taking the SPY, down selecting for say 50 companies, and directly holding the shares.
Of course, this advice if worth exactly what you paid for it
