My knock was a lot higher than 69.. What I did was to pull timing from the whole map untill it stops... this will give you a good idea how much you will need to pull from the inj map later... Once you have worked out how much timing you need to pull set the base timing back to where it was, get a friend to drive the car and in map trace mode pause it when it is pinging...
Go to the appropriate map point in the ign map and pull some timing out at that point... It will take a while on the road so dont rush it... You can add fuel at the same map points to attempt to decrease knock..
I suggest you get a wide band o2 sensor and a A/F meter from say Jaycar.. (not the best tuning tool) but better than nothing... ( I will get flamed now)
I take no responsabilaty if you stuff your engine... This is just what I did to mine to keep it safe until I get a dyno tune at a reputable Tuner...
You can also try running octane boost as tha APEXi PFC is set up for 100 oct fuel until you get it tuned.. Its expensive but cheaper than a rebuild....
Other wise keep of the throttle.. We all know how hard that can be