Ring gear question

Hey guys I have a question on ring and pinion on a Dana 35. I purchased my new jeep in december already built, lifted, geared, 33's, arb bumpers new aftermarket limited slip... etc. However, in my excitement of purchasing the jeep i did not pick up all the necessary receipts and stuff for the work that was done on it from the PO (tried to call him too). So, since I now have 3 broken teeth in my ring gears, I need a little help....
The PO told me they are 4.56's, and I believe they are based on how much it rules on the trail compared to those with stock gears. However, when I popped the cover off to investigate the noise I found no numbers indicating ratio stamped on them. I believe they are Yukons based on what the PO said and on the numbers that were there. Can someone help me figure the ratio based on these #?'s???? remember this should be yukon.... dana 35...
15 YG 42721 304 is the ratio in these numbers? part number? Somone had scratches 288 on the ring gears too... (mean anything?) I was trying to call randy's ring n pinion today and alas they were closed.

If that simple way doesn't work, does someone have a link to a website that explains the ratio calculator based on teeth and pinion (I think it is).

Sorry guys I am learning as fast as I can! :tears: Oh yeah I tried searching too...

Count the number of teeth on the ring and divide that by the number of teeth on the pinion. This will give you the correct ratio.

:doh: Thanks! I thought that was it...