You will want to re-gear. in stock trim the 3FE is a good runner, but between the parasitic drain of the auto and the larger tires, you will not be happy.
for a 35, I am going to say 4.88 is where I'd land. I ran 5.29s on 35s for years and the motor and trans just didn't seem super happy. I just stepped up to a 37 and the shift points and rpm band seems much happier.
When I bought my rig years ago, it was on 35s with stock gears and it was a complete dog. Pulling just about any slight incline, it would be all the way down in 2nd gear and we'd be going 35 up the hill.
you might get by with a small 33 and be ok on stock ratio, but if you get into 35s you are going to want to look at gears, or be prepared to rarely see overdrive.
I tend to agree with
@Marco Lau the 3FE is kind of like the 3.0 of the land cruiser world. It gets a bad rap because it was the last generation before they came out with something better. Everyone loves the 2F in their 40s and 60s, but the 3F is junk. Its not junk, it is what it is, a tractor motor that will pull for days. the old cruisers have never been known for speed, but then they got a 1F, then v8s and all of a sudden people want them to be sports cars. They aren't. A well tuned 3F will just keep on on chugging along.
But if you get into tires, you are going to want gears.