SPX is trading in an impulse move similarly to the Nas100 on the 4 Hour timeframe. Things we know about an impulse move is that wave 1 and 4 never overlaps therefore we can use that idea as an invalidation level for the pattern. Trading the pullback can be tricky considering the timeframe we are at and also the phase but on a lower timeframe like 5 to 15 minutes can be decent personally I don't prefer trading the A wave waiting for a C wave is better, but note the main bias is bullish in general.