I got tired of playing that game. Had a friend install one of Moates G2 adapters. There are two one for .45" spacing and one for .6. On the 1227148 ecms they used both spacings. If your prom holder has open squares in the center of it (on the ecm side) then it's the .6 spacing (from those I've seen so far). The .6 spacings *seem* to be the later production ones.
Add this adapter and a ZIF socket and forget about that silly plastic holder game. It does take some expertise to make the conversion.
Ah, the wonders of forum searches: http://www.turbobuick.com/forums/showthread.php?s=&threadid=122077 is about the last time this came up. John Spina carries a reproduction piece that works. Or, if you have a u-pull-it junkyard handy, you could gather a dozen in an hour. So long as I'm buying something else anyway, the yard I go to doesn't charge for 3-4 carriers.
Thanks for the link, I had searched for "Carrier" instead of "Carriers". Found that 3M now owns the company that used to make them, but can't find them on the 3M website and I don't have a part number, I'm looking to pick up several hundred.
Thanks