I just dropped the trans pan in my work truck to change the filter, After I have all the bolts out that hold the filter in I realized that one is a little longer than the rest, which hole does it go in? There are two bolts that are slightly larger, and 10 or so that are smaller in Diameter. One of them is like 1/4 longer than the other ones. I really wish I would have noticed when I pulled them out, but I was in a hurry. well there you go. The transmission is out of an 88 F150.
the longer bolt on the C6 filter goes towards the rear of the filter. IF you look at the holes for the filter screws....ONE hole is slightly smaller in diameter than the others. That is where it goes. The hole is smaller since that is an alignment hole for the 2 halves of the v-body