The rear proportioning valve on my 1983 Interstate is leaking. I have checked the connections, and it's not leaking from there. It's between the valve body and the bracket holding it to the frame. From reading on this and other sites, I'm guessing that the valve is cracked. I was wondering if it's a viable solution to coat the valve with JB weld to seal the crack. If not, would TIG welding it be a better solution? I am unable to find the valve anywhere for under about $100 and I'm hoping for a little less expensive solution.