This is the first time I am ever going to do a proper conversion of a module...
I was trying to work out the encounter level and reading through the module it recommends 10 1st level characters to 5 3rd level characters.
So is this really a 3-6 level module for 4-5 players?
I'd have to double check, but I do recall that it was a pretty tough adventure, culminating in an encounter against a red dragon. Plus there were some tough encounters just on the way up the hill to the main dungeon (a couple of ogres, for one thing).
Just offhand, though, I'd say look towards converting it around the baseline assumption of Pathfinder games (4 players/4 characters), and then adjust accordingly.
For balance reasons, it probably won't be possible to make an exact conversion; again, those initial encounters going up the hillside may need to be decreased in CR level, or else you'll want to ramp up things at the top to compensate.
Since the adventure is basically a dungeon crawl, you can easily set it up so that it assumes the PCs leave to recuperate for a time after completing levels, to train etc., which should be another balancing factor.
Lots of ogres goblins and hobgoblins.... It also says
Note that if the characters return to
town between sorties on The Hill, certain
monsters are not idle in their absence. In
particular, ogres, hobgoblins, and goblins
replenish their garrisons three days after the
party cleans them out. In fact, there is a 33%
chance the number of ogres, hobgoblins, or
goblins is actually 50% larger than the number
first encountered!
I might use this thread to note the work I am doing on the conversion...
I am thinking 4-6 characters of 3-4th level.
This module is insanely hard.
So where in Golarion do I situate Guido's fort - I am thinking Baslwief.
It is located in the foothills of the eastern Fenwall Mountains in Varisia, on the banks of the Sarwin River.
There is is an unnamed fort nearby...
Hmmm... Baslwief was the first town to suffer the rage of the red dragon Glarataxus
You can also swap a Red Dragon for something like a Fire Drake, maybe add a template. Same overall feel, greatly adjusted lethality.
'Dot' for observation....