1) To upgrade from Alpha one to Bravo 1 do I need to replace the gimbal as well or just drive unit?

2) Where can I get the service manual for Alpha drives?

you need to replace the gimble its actually pretty simple, however if you dont actually need the bravo the alpha will be a little faster.

Do you have an Alpha One or an Alpha One Gen 2 ? Do you know the serial number ? I have them both in PDF. PM me an email adress and I'll send them to you.

What engine you running?

I have Alpha one gen 2. Engines are stock 350 mag.
I do have the serial numbers.

I wouldn't be to concerned about running the alphas on a twin smallblock application in a 6000lb boat. Not that it is a direct correlation but 3000lb/drive behind smallblocks. They have lasted 14yrs so far. Just take care of them. If you start having issues and replacing them every year or add power....then ok. I have seen a 32 Pachanga with big blocks that the alphas have lived behind.

Also I am no drive expert so take it for what it's worth.

I am happy with the Alphas. People in the past have kind of made me think the bravos were superior. But for my application. I think you are right. Im Sticking with them.

Thanks for PDF file of the manual Jim!