I just did mine on my '99 too. I probably spent 8 hours on it and spent over $30 in tools plus $10 more on a tool I returned. I consider myself lucky I didn't damage anything.
The first tool was an OEM brand metal scissors-style, purchased at Autozone, which was so poorly made that it wouldn't close down on the filter inlet and fit under the shell of the coupler.
Second tool was a plastic collar type, purchased at NAPA. This one might have actually worked, but read on...
Third tool was another metal scissors-style, purchased at NAPA. I dressed up the welds on this one and it fit on the pipe and under the coupler shell. I may have felt the coupler release when I first pressed the tool in, but I'm not sure. The filter did NOT slide off easily. The coupler retention clips really had released at some point, but it took a lot of force and some twisting to pull apart.
After I got it apart I discovered the inside of the coupler shell had rusted and was an extremely tight fit on the filter pipe. Then, of course, the new one wouldn't just fit. I ended up pulling out two o-rings and taking a file to the inside of the coupler. Putting the o-rings back in was a challenge. In the end, I persevered.
So, don't feel too bad. I think barring problems like you and I apparently had, changing the filter is usually really easy.
BTW, the other important part about changing the filter is to depressurize the fuel system first. I disconnected the fuel pump cutoff switch below the glove compartment behind the carpet with the engine running. Once the engine stalls it's pretty much depressurized.
Take care,
Jim