I've looked at the WIX filter site and at the specs for the 51334 filter that's for the 4ZE1 engine. There are specs on the thread ( 20mm X 1.5 ), the gasket size, and the pressure that the bypass valve should open ( 8 - 11 PSI ). There is also an anti-drainback valve on this filter.

So, we know the specs on the filter, all we need now is a way to plug them numbers into a search engine and come up with an alternate filter that is physically bigger.

Haven't found that yet...

I think there's plenty of room on the 1st Gen (4 cyl) Troopers to get a bigger filter on there.