The 68 mustang pan won't work even if you get the dipstick figured out. The front sump is in the way of the front axle.
The rear sump Bronco pan is an obvious solution, but there are plenty of Broncos running around with late model fox mustang oil pans, they work fine. Just have to watch the oil change mess as one of the drain plugs runs across the steering.
Late model Explorer pans are also known to work. It has an extra quart of capacity like the original Bronco pan.
Whatever pan you get needs a matching oil pickup. Even the rear sump pans are different. Bronco is different then mustang which is different then explorer. I haven't checked but I expect even an Explorer steal pan is different than an Explorer aluminum pan.
The dipstick also has to match the dipstick tube as well. The mustang and explorer both use the same hole in the block. The Bronco original pan uses a dipstick that attaches to the pan itself, so the hole in the block needs to be plugged. There is a tiny cup plug (freeze plug) that you can get for under $1 that fits good and better then trying to fill with epoxy (that probably costs more)
