Yes, in almost every case, you have to remove the pan to change the filter. Only in an industrial application have I seen an automatic transmission with an external filter. Some transmissions have drain plugs, but not many. You have to pull the pan anyhow is the thinking. It's not hard, but as mentioned, it can be messy if not done correctly. You're going to have to loosen the pan, do not remove all of the bolts yet, to where hangs down in the rear and let it drain. Once finished draining, remove the rest of the bolts along with the pan. Your filter is a flat looking screen held in place by screws, and, like my Jeep, you might have an additional spin-on filter too. At this point, the most important thing is absolute cleanliness! The tolerances within the valve body are such that the most minute speck of dirt can be catastrophic. Once your filters are changed, clean all gasket surfaces, apply the appropriate sealer, a new gasket, and replace the bolts tightening in a chris-cross pattern evenly all the way around until to torque specs. All that's left is to refill with the proper fluid to the appropriate level, and you've now changed your transmission oil and filters.