my first engine rebuild (318) advises

I would be using 98 at those prices as well. Also, (I'm sure you all know) 98 in euro is same as 93 in usa.

I would aim for 9.5-10:1 comps on iron heads using that fuel. If you're going to put money into a set of iron heads I would also suggest getting the edelbrock heads. They are not that much dearer than reconditioning and porting your iron heads.
But you will need to strip down the edelbrock heads to check everything is right, this you can do yourself.
By using the alloy heads you can up the comp ratio to say 10.5:1 on 98 (and save 30lb over the front axle).
But check the deck height, the 318 I did varied greatly from side to side and front to back.
Also, what shape is your distributor in? I had mopar electronic on my 273 that was fairly old, I replaced it with one of those big cap chinese hei distributors from ebay and it was a major improvement.