Honestly, if you want to do it properly you need to go through and unplug each plug and put dielectric grease in every engine and transmission plug and as a precaution/preventative maintenance, any other plug that you might submerge. Keeps connections strong and plugs corrosion free. I personally didn't just extend my breathers, I ran new vacuum line from the rear breather to a Barbed T fitting and plumbed it to the transfer case then to another T into the transmission breathed into another T into the front diff breather and up as high as I could in the engine bay to a diff breather cap. I planned on running this to the air cleaner, but haven't got around to removing it and brazing in a barbed hose fitting. Then of course a well sealed properly installed snorkel as mentioned. As far as the dizzy goes, if there is no silt or salt in the water you should be alright. It's the silt and salt impurities that mess with the conduction. I had my dizzy cap sealed with FIPG for a while, they don't last nearly as long because the internal heat build up and cool down create internal moisture which causes corrosion and oxidization internally. A lot of caps have a rubber breather cap in the center, if your cap has that breather you can seal the dizzy with FIPG and when it comes time to cross, pull that rubber breather off and put a vacuum cap over it for the crossing. Other than that, make sure your door sills and seals are clean and that your seals are in good condition, gotta keep the water out of the cab and away from the electronics. Other than that, keep her slow and steady to create a bow wake to keep as much water as possible out of the engine compartment and away from the clutch fan. Or buy the wonder bra for the front Lol.
