Hi Brooke, yup definately shorten the am nap.
I actually would start with 1 hour for the am nap and then leave the 2nd nap at about the same A time.
so maybe:
wake 6
nap 9:30-10:30
nap 2-3:30
bed 7:00/7:15
if this works, you have shaven 1/2hr of sleep off of your day and hopefully he will add it to his night,
if he is still fighting the pm nap, you just shorten further. 40min am naps didn't seem to work, so we actually went down to 30min and then he was asleep by 3hrs later for 1.5hrs long.