flubyux2 said:the rusty nipples are coolant lines. leave those open.
there is another nipple under the #1 and #2 runners and a nipple on the metal coolant pipe under the rear runners, join those 2 nipples together w/ a 3/8" fuel hose and clamps.
this will keep coolant from circulating in your ISC and TB and keep it cooler when driving. wards off heat soakery.