BunF, yes the total seal rings are a must
I won't bother with the OEM pressure sealing ring, as it's a poor choice of material & always NEVER gapped at the factory correctly, hence lots of cases of ring land damage by pre-det.
I was going for the first ring also, but just too costly.
Just waiting to book my shiteheap in now....
but I'm in no rush.
My list of parts do differ tho' as I'm going for reliability & better flow
but I will probably have to dump the OEM ECU, just not up to it
...interested to see your results