The heater bypass valve box was replaced with a stainless steel one from plane inovations llc earlier and I had adheared it to the firewall with supplied rectorseal biotherm and clecoed. I just now got around to ordering the required stainless hardware called out on the instructions and installed them today. I also scraped a bit of the sealant that had oozed out on inititial install so that the door flap would close tight and complete.