unfortunately, this is still user error.
I use those very same wires on all my ford gassers.
You get MUCH better service fromt he brass pieces if you use a pair of wire cutters and snit them off the sprue, trimming the lil connecting pieces that will catch and cause difficulty in insertion and removal.
Also, trimming the wire back about 1/4" from the end and slipping it thru the smal perfed triangular hole at the base of the clip, and then soldering it, and trimming hte end yeilds a STRONG and good electrical connection. I've never lost a brass clip once soldered .. the go in and come back out fine.
to slip the wire thru the boots, use a bit of silicone.. or even vasolene or that fancy dielectric grease some sets give you.
as with most things in life.. there is no free lunch.
minimal effort yeilds minimal results..
extra effort yeilds extra results.
Not what most people want to hear.. but i've found it to be true.
I havn't kept up with my count lately.. but I wager i've got over 20 tractors, and only a few are diesel.. the rest are gassers. they are ALL using those cut to fit plug wire sets from tsc or similar stores.