SU banjo bolts - using the wrong washers?

After setting floats, removed the rear banjo bolt to get the hose barb at a better angle. Afterward it leaked. Leaned on the wrench until it was only a tiny leak, it didn't drip but it felt slightly damp.

So today, finally fixed the leak I think. Used two composition washers from the carb tune-up kit from MSA, don't know if that's what they're for but they fit. Also used the aluminum washers that were on there, on the outer ends. It still leaked until I sanded both sides of the inner aluminum washer.

Still had to use what seems like too much torque (but not as much as I used last time) to get it to stop leaking. Something's wrong there.

Are there some other washers I should be using? Would be OK to put some sealant on the washers? Not much surface there.

Seem to remember a post about this but couldn't find it.