I've read that Mike Ross of BE&A can attach them. Depending on where you live shipping your stuff to him might be prohibitive. The following information was copied (and slightly edited) from another forum that was posted by him.
I have all the tooling and press here to correctly install them. If you've purchased new pigtails and can't figure out how it install them in your original housing? Send them to me. If you haven't removed your original pigtail, don't, I'll do it here, you can easily break the lip on the housing the pigtail is crimped to.
Installing pigtails with the correct tooling is very simple, the turn around time is same day, just cover the USPS shipping.
I also have pigtails here I can sell you.
Michael C. Ross - Owner
B/E & A Restoration Parts, Inc.
8801 Norwalk Road
Litchfield, OH. 44253