I'm afraid I do not understand the explanation of this egy. If your day begins at 5 pm ET, then by definition of the very first bid/ask that transactions at 5 pm comprises the high/low of this day. Every move after that will make either a new high or a new low -- how else could you decide whether it's the day's low or high? If we're currently searching for DAILY high/low, what difference does it make if we're about the 1 hour chart or the chart?
On either chart the price will be the same, though it's the high/low of this day it also will be the high/low of this hour and the minute. You mentioned putting RSI and the MACD on the chart, but you didn't explain what we are supposed to be looking for with those oscillators. What are you up to Merlin?