Aux Gas Tank sending switch tank selector & double 3 port valve

[greedy geezer]

I have been monkeying with this on my 72 c20 the switch does work but every time I change it it it takes a lot of messing around to get the correct tank level so at least it works that is good , after excising the double 3port valve and running out of gas once night on both tanks at once, it now will separate the tanks everything is working but the switch on the dash still giving me aggravation anyone know if I can get a replacement or fix the one I got this seems to be an issue that has been talked on over the years on old threads