2001 Gen 1 Power Steering Light + C1513

So just a few months after getting the front CV axles, lower control arms, ball joints, front struts, links, tie rods, and a new 12 volt and inverter coolant pump... now I get a Power Steering Light & code C1513 and no power steering. At least until I 'reboot' the car by stopping and restarting.

All told I probably shouldn't have bothered doing the front end work, but.. I had hoped things would settle out and I wouldn't need to do anymore big repairs for a year or so.
It's over 325k, and on the third remanufactured battery pack, but had been running fine for 5 or more years - if noisy and a bit rough the last year or so...

I'm considering getting a used rack and pinion off ebay for around $150, but - while my mechanic is fine, he's not a hybrid guy, so I wonder if this would be an overly difficult job for him. I've been lurking on these boards for a few years, and saw some discussion of needing to replace an ECU to get a used rack & pinion to work, not sure he'd be the best mechanic for that sort of thing. (Mind you, he did fine with the inverter coolant pump job, but there wasn't really any electronics going on there.) Swapping out the rack and pinion is beyond me, I was impressed with myself for getting the 12 volt swapped out with help.

So my question is, can a reasonably good mechanic, but not a hybrid expert do the rack and pinion swap, or do I need to take it to a hybrid shop?