Newbie Looking For Help on Spinning ICE without Firing

Question: How do folks spin the ICE without starting it? Is this done as a hack? (e.g. using an external relay to switch off fuel and/or spark) Or as a CAN message over the bus? (i.e. is there a CAN code for "spin engine but don't run it").

I'm soon to become the owner of a rolling PHEV experiment - err, I mean a 2004 Prius which I shall promptly turn into said experiment. Yes, I realize it's "all been done before" but that doesn't stop folks climbing Everest, right?

My current plan is to do a large LiFePO4 pack (60Ah * 200V = 12 kWh). I plan to develop a CAN Bridge to split the CANBUS into two separate networks so that I can inject and alter messages between the battery subsystem and the rest of the network (that's if I leave the NiMH in place - if I do a complete pack replacement then I guess I'll be doing my own Battery ECU - but that sounds like more work still!)

I want to try and get a 70mph capable EV like the PICC25 kit but with significantly better range. I'd simply buy the Ewert's HEM - but they don't sell it separately. 64 60Ah cells should be less than $5K. I don't want to shell out an extra $8,500 for the PICC25. Besides, I'd rather do it myself.

I've been reading up on the PSD and the MG1 RPM limits. This page is great: "Toyota Power Split Device" (forum won't let me post a link yet)

Hence the question: What's the best way to spin the ICE without firing it?