Hi Kara!! I'm so happy for your long night!!

Some thoughts...
Having a long am nap and a long pm nap is something very personal. I mean, you need to decide which way suits you and your Ds better. We have a long am nap b/c I love the freedom of going out during the afternoon and being able to have a short catnap on the go. Also, Patrick can handle long As first thing in the morning, so that helps us in pushing the am nap later when it starts getting shorter than 2hrs.
What I would do is choose one plan and stick to it for at least 3 days and see what happens. So, if you decide to have the long am nap, go for it, but stick to it for 3 days and see how your DS reacts. If it doesn't work, you can always go back to waking him up from the am nap. The only problem you may encounter with the long am nap is that your DS may refuse to take the pm nap once he handles longer As, so you will have to move bedtime earlier. Also, remember this is a matter of trial and error, so you will have to experiment with different As until you find the right ones. When having a short pm nap, the next A can be the shortest b/c babies get more tired after a short nap. iykwim?
Do you think your DS will be able to handle 4 hr A time after a 45 min nap? If so, then go for a long am nap and a 3.15-4 pm nap. If after having a 45 min nap, your DS starts getting tired earlier, then you will have to put him down a bit earlier to bed. May be 7.30 pm, and then you can try to push the pm nap later so he doesn't have a long A before bedtime.
Patrick has a 2 hr am nap and a 40 min pm nap, and he can only handle 2.75 hrs A before bed after a 40 min nap, so just be careful not to put him to bed OT after a short pm nap.
And yes, you run out of hours if you have long naps and long As! So, first choose the way you'd like to go and then we can think of a routine. What A times can your DS handle happily? 3.5 or 4 hrs? What A time gives you a long nap? How long?
Hope this helps. Alexa