I have a Toro Titan and I am guessing the control arm connection to each of your hydrostatic transmissions is the same on yours. The control arms would connect to the transmission near the rear of the mower. A photo of mine is given below. If it does look like this, the bolt on the upper right (the one on the control arm rod ) can be adjusted to control both speed and creep. Twisting the bolt conterclockwise (looser) makes this side go faster, clockwise would go slower. This will address steering--either slow up the fast side or speed up the slow side. Just adjust 1/2 turn at a time as it is pretty sensitive.
Creep is another matter. I think Toro cut some corners here, as, at least on my model, this same nut addresses both creep and speed/steering. From my service manual, to adjust creep you need to jack up the back of the mower so both wheels are free. Then I put a bag of sand on the seat so I could start the thing. Start and then put in neutral. Twist the same nut I mentioned above (control arm nut) until the wheel does not spin.
The big downside is that if you stop creep you also will slow down the max speed. This is just because the same rod controls both, and, at least in my mower, the forward motion of the steering arms is limited by the metal frame around them. This kind of bugs me, as it's a clear design tradeoff. Many other mowers have a separate Return-To-Neutral adjustment available. I chose to live with a little creep to keep my speed up.
[I am really tempted to take a grinder to the metal frame the limits the forward motion of both steering arms. I bet removal of 0.10 inches would be enough. This would let me stop creep and go fast! Damn the warranty, full speed ahead!!]
