
Turning around twice seemed awkward, so I decided to fly out towards the northern DME arc and join the IAP there. The MSA was 4300, and I had begun descending as soon as I was within 25 nm of AST, so I was at about 4300 before reaching the arc, and once on the arc, I descended further to the suggested 4000 feet. It was a challenge to hold the arc but I did okay. As I approached the ILS localizer centerline, I turned to the west and armed the AP for the approach, which it immediately captured. The approach thereafter was routine, with me turning off the AP about a mile out of the field and completing the landing by hand in slightly gusty winds.
I'm trying to find out how this procedure should be flown. I tried asking about it on a newsgroup, but that was the usual waste of time because there are very few qualified instrument pilots on the group, and lots of noisemakers. I'll try asking in some other venues. The documentation I have (FAA manuals and such) don't make it clear how I should fly this, or I've missed the relevant passages. I've included a picture of the plate here (it's government-issued, not copyrighted) in case anyone would like to send me feedback with suggestions.
Later I flew back from Astoria to SeaTac, but that was easy. I proceeded in over OLM and received the Elliot Visual, which was pleasant to fly. I parked over in the transient area now that the new runway area is finished (I've also routinely parked in the cargo area north of the tower, but it looks like GA aircraft are expected to be in the transient area instead.)