Well, now, then, there, ummm ... I've done it like this in the past (and it always worked fine, with no problems whatsoever) ...
Entering Epcot at opening time, I stroll to Soarin', paying little attention to the people who are running ahead of me, and ride it when I get there, using the standby line. If the fastpass machines are open, I go ahead and get a fastpass before riding; or, if not open then I get a fastpass after I ride Soarin'. (Works either way, just the same in my experience. Usually the fastpass machine is up and running when I first get there.)
Then I stroll over to the Test Track. (No running for me.) Using the single rider line, I ride Test Track twice. Then I meander back to The Land and use my fastpass for my second trip on Soarin'.
It's never been a problem at all for me. Sometimes, I ride The Land Boat Ride before that second Soarin' ride. Makes little difference, and the whole thing does not take up a long time either, and no running or even walking fast.
Enjoy.
Entering Epcot at opening time, I stroll to Soarin', paying little attention to the people who are running ahead of me, and ride it when I get there, using the standby line. If the fastpass machines are open, I go ahead and get a fastpass before riding; or, if not open then I get a fastpass after I ride Soarin'. (Works either way, just the same in my experience. Usually the fastpass machine is up and running when I first get there.)
Then I stroll over to the Test Track. (No running for me.) Using the single rider line, I ride Test Track twice. Then I meander back to The Land and use my fastpass for my second trip on Soarin'.
It's never been a problem at all for me. Sometimes, I ride The Land Boat Ride before that second Soarin' ride. Makes little difference, and the whole thing does not take up a long time either, and no running or even walking fast.
Enjoy.

.