Hi. I have the 17 inch Blackstone and would love to make this mod, but was wondering where you found the mounting brackets that you used under the Blackstone that slide onto the rails?
They usually come with the grill. You can buy this grill cheap, keep the bracket then try to sell the grill at the various camp grounds you visit.
I took them off the original BBQ. But for the 17' griddle, Forest River is now providing that in place of the BBQ. I saw a kit at a dealer, Haylett RV. See link to YouTube video.