Any ideas how I can fix fuel inlet leak on my slant?

The thing is, the brass part that screws into the carb IS THE seat for the "needle and seat." So you can't just epoxy it in unless you are willing to gamble on "never having to remove it."

You might try several wraps of teflon tape. "I don't know"

In "yesteryear" it might be you could have bought "oversize" seat assy to "repair" it but no idea if or where you could do so now