62 gmc ho33?

[62jimmy]

Hi, new member here and starting to collect parts for my 62 gmc project truck. I posted this on another GMC site with no response yet, so I thought I give it a try here. I have been thinking a lot about the drivetrain combo I will use and crawled under to id the rear axle. I was expecting a Dana 44, but according to the pics in my 55-62 illustration manual it is an ho33. I am not familiar with this rear. My questions are
1. Is this a strong rear, I am planning 300-400hp ls engine?
2. Are rebuild parts available and other ratios?
3 are there any stamps on the case to help me Id the current ratio
4. Did these rears come in anything else that the pumpkin would interchange with, I seem to remember my uncles 61 409 car having a similar setup.

Any help would be great!
Thanks,
Jeremy