^ I posted about the duct tape and sponge then removed that from my post because heat, and the tape adhesive will probably get dissolved by the oil.
?? We're talking about spreading the RTV on with the pan still installed (depending on where the crack is), minimal tools needed, just to drain the oil enough, a good cleaner, and something to spread the RTV on and squeegie it into the crack, like a credit card, a playing card, a piece of a plastic container lid, a stick, your finger, someone else's finger, someone else's toe, an eagle feather, a leftover pancake, the tongue from an old shoe, bologna, an acid brush, or you could 3D print something.
Wait, the obviousness of it escaped me. Use a day old slice of pizza.
The key to this is surface prep. Where it's parked, what tools you need... would take a lot more consideration of these things to put some catch pan thing under the pan.