Slant 6 intake/Exhaust Install

Any suggestions in installing a slant mast exhaust and a aluminum intake. Made the swap last week and have a massive exhaust leak. Seems to leak where the intake mates to the exhaust. Used the staock sleel gasket. Do they make a fibre gasket? Used a stock gasket and I am thinking of using a Remflex. Any tips or suggestions


I'd check for flatness ? if ok then leave the intake and exhaust mating bolts loose until you get the manifolds mounted. that way the manifolds could slide to align a little better to the head,then tighten em up. the last set I did required me to take the set down to a machine shop and have it milled to fit with the aftermarket manifold. 30thou cut got it flat and it still hasn't leaked with the stock gasket.
I have an offy dual 1bbl manifold going on the 66 dart I'm working on and the manifolds look really close so I'm just going to use the thicker remflex gasket to seal this engine up on this engine.