A more traditionally Buddhist description of something very similar (which in my opinion is really the same thing) can be found here, if you're interested in that sort of thing:
Middle-Length Discourses of the Buddha, number 19.Scroll up to the paragraph above the one the page loads at, and it will look very familiar: It's the formula for the first four jhanas, followed by the description of the Buddha viewing myriad past lives. The Buddhists consider things like accessing the Akashic Records to be a form of siddhi, and the fourth jhana has traditionally been considered the base that the siddhis are operated from. I've heard it said that this tradition goes back to the Visuddhimagga, but I think that this sutta indicates otherwise. The use of the fourth jhana to access "knowledges" then probably dates back to the time of the writing of the biography of the Buddha's enlightenment at the very least, and if the description is historically accurate, then to the time of the Buddha himself or earlier. At any rate, historical concerns aside, the fourth jhana and similar concentration states have been used for this kind of thing ever since, so they probably work really well.
More modern instructions would be found in the concentration section of MCTB, which is
here, about halfway down the page. Where it talks about formulating your goal in Buddhist Magick, your goal would be accessing the Akashic Records. You said you had pretty good concentration skills (jealous! clearly, I lack both concentration AND mudita) so the formular presented should work pretty well. If not, then I'm sure someone here can help you with this! You have the concentration it takes (or the ability to develop it) so it should just be a matter of getting the mechanics right so that you actually have the experience of accessing the AR.