nope, put it on the block, it'll stick. i would set the pan on the block and outline with a marker where the pan sits so you put the sealer in the right places, also look at the ends to see how much gap to fill. hump it up over the crank when you apply the bead and make sure to apply plenty. i would let it sit overnight personally.
reason i had to take my pan off is i didn't follow the pan rails well enough around the corners.
