racegate
I have been using a racegate for 4 years. My crossover is not a factory piece. A factory piece is double walled. Not saying you can/t weld it in like I did, just that my crossover is single walled 14 gauge tubing, but run in the same location as original. My gate is welded in just below the driver side flange ( header to crossover) about where your left foot rest. I made a short tubing nipple with mating flange. With exhaust system on car and gate bolted to flanged nipple, hold it up to crossover and locate and mark best spot, take into account the sterring collum linkage. I welded mine on them went trough nipple and bored the hole. Using a die ginder I radiused all sharp edges. Hope this is what you are looking for. I later piped mine into the exhaust system. Ran it for 3 years just dumpimg to atmosphere. Makes a fluttering noise under boost. Some people don/t like the noise, didn/t bother me but my Darling didn/t care for it. I heard a turbo guru (at a tech session) say that a wastegate will not work on the crossover. I didn/t ask for any details or ? him as I thought it would be fruitless.
I don/t see any other place to put an external gate on an 84-85. That looked to be the best spot.( for me anyway)