Lots of nice engines have been built that way. With an open chamber head (no quench) compression in the low to mid 9's usually works well without detonation. Studs do help retain the main caps but in a mild engine not too important. When adding studs, line hone is recommended to bring the bearing bores back to round with the higher clamp load.

On the heads... if you have a set of 906's in good condition makes sense to use them. If you don't buying and rebuilding the heads or buying a quality re-built set will cost nearly as much as or maybe more than a new set of aluminum heads.

My suggestion would be use aluminum (eg Eddy or Stealth) closed chamber heads and build so the piston is at zero deck. With a common .040" gasket you will have perfect quench. You can push compression to 10-10.5, get more power and better mileage.

Getting block top decks machined square and deck height measured by your machinist is the first step in a "quench build".