You can see the nut,tab washer,bearing carriers,xr tool,

Christian,
With that kind of power and weight, you shouldnt be eating up gears in 20hrs. The 30" B1 may be the cause. I am running almost 6000 lbs using a 26" B1 (stock) and have run 87.7mph. Didnt have the datalogger on and never saw the tach (probably around 6300rpm), but have 300hrs on upper and lower gears. I havent inspected them from last year, just went ahead and built a new drive. Now the motor is down and had back surgery, so looks like I might be ready next spring when gas is $12.00/gallon????

How tight can you wind that 525EFI? And can you get close to it with that 30" prop?

At good day (not too warm) 5200 rpm 78 to 79 mph ....i`s a lab finish ....and this is picture of the lower we open this morning ...found nothing special ...its look the part came from the upper

Sorry to misleading you , it`s my old lower with a upper of 20 hrs .....we found other piece of metal at the coupling assembly (merc number 88243A3) ...maybe the piece come from he needle bearing (merc number 31-843240)
i will kep you posted , thanks for all your help
Regards
Christian

thats weird,let us know when ya find out:D