I've been using EMPI since G. Burg as alive, Dino Dyna Sore and the Inch Pincher were active competitive VW Race Cars. I've installed my share of "Extractors" but if you are installing them your selves, pack a lunch. The #1 and #3 "factory fresh air/heater boxes" are roughly 1/6"+ out of alignment. You just need to be ready, "they will interface/fit, just attach one side and then "Persuade" the other. Be sure and have your lower exhaust fitting/fasteners ready to make this connection. I use "never sieze" on the head studs #2 & 4) before snugging fit. If you have pneumatic tools available, it will save time. I personally wrapped my header with "header insulation wrap" prior to insulation. It will fit, just make it work...
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