Fram filters have been getting a bad rap for internal paper end plates, which apparently is at least partially deserved. This was a cheapening of their construction that was done about 15 years ago. A lot of people avoid them now.
<span style="font-style: italic">Consumer Reports</span> ran a test about 20 years ago on oil filters. Their conclusions were that the best filter to use is the OEM filter, but only the OEM filter from the vehicle's manufacturer (<span style="font-style: italic">i.e. never use an AC filter in a Ford, etc.</span>). The Fram PH3600 is their replacement for the Motorcraft FL-400A. I've been using the FL-400A for a few years now on my TR6 spin-on with no complaints.
Other filters that can be used with spin on adapters, as per
mgaguru.com:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Filters which can be used with the hanging spin on adapter:
AC PF-56
AC PF952 (short)
AC Delco Ultraguard Gold UPFL-400A
Bosch 72-143
Bosch 72129 (short)
Bosch 72161
CarQuest 85516
Champion C104 (short)
Crosland 529 (short)
Fram PH3512 (short)
Fram PH-3600
(Fram PH-3614)
Full PH-400
Halfords HOF200 (short)
K&N HP-2009
Kralinator L38
Lee LF-42
Mann W719/36
Mobil-1 M1-209
Moss 235-950
Motaquip VFL123 (short)
Motorcraft FL-276
Motorcraft FL-313 (short)
Motorcraft FL400A
NAPA Gold 1516
Purolator L10101 (short) (was PER 101)
Purolator L20064
Purolator L20195
Sears 45197
STP SO-400
Unipart GFE173 (short)
Unipart GFE443
Wix 51335 (short)
Wix 51516[/QUOTE]