I have not had any problem any of the ignition terminals I brought so far. Now you do know the 33-351 are for 16-14 ga only? There are different ones for 12 ga and for 20-18 ga.
For the open barrel Packard (GM, Delphi) F56 you need a proper crimper like the Accel 170036 that does open barrel crimps. Now they will set you back $70-$95 but are well worth if you do a lot of any wire crimping. Will do both insulated and non-insulated plus 7-9mm spark plug wire terminals too. Just won't do battery cable lugs. The crimps are factory style. Just a small learning curve as terminals can be only crimp one way or they be crimped improperly.
Might seem expensive to some but once you get use to them you will wonder how you manage without them or at least I do as the those el cheapo crimpers that come with solder-less terminal kits are worthless and hard to get good crimps.
I got mine back in Nov '16 through my Smile Amazon account with free 2 day shipping.
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