I routinely crossed a creek that was 4+ feet deep when I was out wheeling in my junker '73 Chevy 4x4 back when I was young and stupid....
I did a few things that made it possible...
*Electric fan with master switch
*watertight distributor
*go HEAVY on the dielectric grease in the spark plug boots. Both ends.
*relocated the ignition coil as high as I could on the firewall
*doubled up aircleaner to carb gasket.
*factory air-cleaner, with re-routed snout to breath from the highest part of the firewall
*extended diff breathers with filters
Oh, and.....
*New door seals :snorkel: