How do I know the price ahead of time if I trade a mutual fund in my 401K

Not happy with some of my investment allocations (they are not terrible but I realize I could make better choices). I am 5-10 years from retirement and still interested in growth (not interested in moving to bonds etc).

I need to move about 200K into other investments within my 401K, not all at once obviously. When I buy a stock or an ETF, I know the price at that moment. With a mutual fund I have no idea until the close and then it is too late to get that days price. I am not trying to time but it would annoy me to lose money based on trading today instead of tomorrow or the next day and it will add up. How can I guesstimate the price of a mutual fund at 2:30PM during the trading day (investment directives have to be in before 3PM).