A 1-7/8" OD x 1-7/8" OD exhaust tubing adapter with a pipe coupling welded inside one end, and the other end modified with six 1/8" x 1/2" slots and clamped to the intake manifold with the original air cleaner clamp. The Solberg F-19P-125 screws into the top.
Permission is hereby granted to at least chuckle at my second MIG welding project (And never apply black oil-based enamel in a very cold cellar):