Regarding the pinging, have you tried a higher octane fuel?
I did my apprenticeship at a suby dealer, and at the time (bout 99) my brumby had done about 10,000km, (yes, only 10,000km) and that used to ping. Took the boss for a ride and showed him the pinging... Pretty normal for one of these he said...
Fast forward to late 2000's, I was at a Nissan dealer, and yep, the petrol V6's like to ping on Aussie fuel...
Fast forward to now, and the wife bought new 2014 Impreza, and guess what? It pings... Had it in for some warranty work just before the warranty run out, I ask, is there an ECU update, this thing pings on a hot day... Guess what??? Yeah that's normal!
I also have a VL turbo... yep that pings...
And a GTR skyline... that pinged hard... and broke a piston

but all the others never had damage from pinging.
Alot of it is due to Aussie fuel being junk. 91 is going to be outlawed in the near future, and it's probably not a bad thing: The emissions are bad, it kills catalytic converters..and imported cars hate our 91.... Ha, all car's are imported now... No more aussie cars.
As for power steering, I have mates who use the astra electric hydraulic pump in their modified cars, I'm thinking that's how I'll try to put power steer in my brumby. Haven't looked too hard into it yet.