I'm going to keep updating this post as I find information out...
I attempted to cross a catepillar filter (the high efficiency 2 micron fuel versions) and found none of them will work... several have the correct thread, but are 5 inches in diameter and 11 inches long... a little too big... none of the cat hydraulic filters cross either. Too bad because I believe these to be better than Fleetguard (2 micron absolute).
So, as of right now... (keeping with the smallest micron ratings)
HF 6604 is a 3 micron... fleetguard only... about $45 from a volume dealer.
HF 6607 is a 6 micron (at 75% efficiency)... fleetguard only (but they also have it down as a 3 micron in their literature???)
FIL1202 is a 5 micron (nominal) from NAPA which is also a Wix51202.
FIL1724 is a 10 micron (nominal) from Napa which is also a Wix51724.
Then there are the Baldwin BT372-MPG which is a 10 micron (nominal)
and the Balwin BT37210 which is a 5 micron...
I have found others... I know for a fact that these are the same filters used in a lot of John Deere tractors... so keep that in mind when filter hunting... they most likely can give you a Deere filter in a pinch.
The Wix51202 can be had for around $15 at most Wix dealers... I bought one from the local parts house last night as a back up.
The sites I used were Napa Filters (
www.napafilters.com), Wix Filters (
www.wixfilters.com), Catepillar's site (regarding filters), Fleetguard's site (regarding filters and literature), Baldwin's site, and several others... there are some really high end filters out there (down to 1 micron), but I didn't even check with them because they are either dealer only, cost prohibitive, or overseas.
And Napa's and Wix's sites are very similar... wonder why?

But they actually give dimensions, pictures, flow and burst ratings as well as microns and are very useful in that respect.
And there is very little in the way of replacements for the screen filter... only Fleetguard (FS1023), Baldwin (BF7760), and DPP have replacements... there is a Napa (3691) that will fit, but has no drain... I also found another napa that will fit (don't remember the number)... but it filters to 15 microns but does have a petcock drain... really a "combined" unit.
steved