Alternative for Proportioning valve

I have a 72 Dodge Demon I have installed a hydroboost system with factory 74 front disk brakes and drums on the back . I am on my 4th proportioning valve I have installed two Chinese piece of junk both leaked all over and have rebuilt to factor valve first leaked internally the one I have installed now has worked but now I have a light don't know if I have a leak internally or if the small shuttle value piston has set it off . I'd like to find alternative the proportioning valve . Any one have any ideas.
Thank you for any replies Harold