I did this conversion a while ago, and stored the data on a spreadsheet. I don't think I can attach a file, or I would.
Anyway:
You don’t need to do much conversion. I just plugged Pathfinder stats for the existing monsters. So where the module says "4 ogres" just use ogres. The encounters have some diplomacy, but mostly are combat. There are very few traps. The encounter levels are pretty consistent in the modules. The modules are about as old school as you can get, so you may want to rework treasure.
Also, there are a lot of detailed areas in these dungeons; players were not expected to explore everything (although many try).
Levels:
Darkness over Sterich This lead in scenario is not necessary, but can be played out. There's only a few encounters, and they over around CR 6 - 7 on the average.
Steading of the Hill Giant Chief Most encounters are CR 6 to 10. Encounters above those levels are something the PC's should avoid. A party of 4 - 8th level characters on a 15 or 20 point build will handle this fine (if they are intelligent). I estimate the party will earn about 300,000 XP (total) in the scenario (about 500,000 is possible, if they do everything right). Expect the characters to gain 2 levels on slow or medium advancement rate.
Rift of the Frost Giant Most encounters are CR 11 to 13. There are a lot of CR 13 encounters, but very little higher than that. Again, there are a lot of encounters (about 48). You probably want a party of 11th or 12th level characters. I estimate the party will earn around 500,000 XP (total) (about 800,000 are possible). Again, expect characters to gain 2 about 2 levels. Possession of fire, heat, or anti-giant weapons could make this too easy, but it's a way to buff up a party that is otherwise too low of level.
Hall of the Fire Giant The encounters in this one are all over the place. Most are CR12, with a normal range of 10 to 13, but a substantial number of CR 16 encounters. After the more consistent Frost Giant adventure, players will find this one easier most of the time. Just the result of changes in the system. However, there are a lot of encounters – you can keep the danger level up by not giving them opportunities to rest and recover very often. I estimate the party will earn about 1,250,000 XP, out of a possible ~2,000,000 XP. Again, enough to raise them 2 levels on a medium or slow advancement rate.
Will your party be moving on to the Vault of the Drow?
