duel fuel tanks - so multiple filters...they need replacement for sure ....
Well ......................
i would ABSOLUTY start there 100% !
easy low cost , ease your mind solution , there is a solid 51% chance ,
1 0r both are clogged ?
why u ask ?
because a rear dual after market tanks in older trucks tend to rust badly inside and cause issues like u describe in detail above
also , possible a original 1976 tank can be compromised too ?
if u replace both / ALL fuel filters , with the ones in my Below link , and you still have isssues , then at least you know for sure , its NOT a Fuel Supply problem , and can move on to step # 2 in your diagnoses etc ...........
i highly and always recommend TOYOTA's Largest capacity and largest filter media element Carburetor Fuel filter they offer ,
its also transparent so u can see any foreign matter inside as u run the engine ect collecting and then possibility then confirm a possible bad tank or tanks u may have ?
Please Explore the Link Below , and let me know if i can further help in any way !
kindly matt
click link here :
Genuine KYOSAN OEM TOYOTA MADE IN JAPAN Fuel Filter - FJ40 FJ45 FJ55 FJ60 - Fits : All 2F Engines 6/78...
vintageteqparts.com