My only advice is CLEAN..... CLEAN..... I mean CLEAN off both the head & intake surfaces.
Permatex makes a spray on "Copper Plate" gasket sealer that I have used with great results.
Also it would not hurt to "Gasket Match" your intake & head ports since you have everything apart.
Just be careful if you haven't worked on aluminum as it grinds easily with a good rasp bit.
and don't make it baby but smooth, a little turbulence keeps the gas suspended in the air flow
and helps vaporize it.
Smooth runners are for High RPM racing apps.
Helping that little 1.3 L breath gives it a little more power.
CAPT