Me three. What is a performance fit? Or do you mean you are asking about the performance of the Delphi filter and how it fits?
THere are filter cartridges available from mfgrs. such as Baldwin, Wix, Fram, Purolator, Fleetguard and so on for the typical filter canisters on the Ford Lehmans.
If you are having trouble finding the Delphis then ask yourself why. I'm not suggesting they are junk at all but the distribution may be much more limited than the others.
I have never even heard of Delphi but again that may be regional.
And yes to contacting American Diesel as they are still the Lehman gurus.