Z1 6 Speed Transmission Conversion

As winter slowly approaches I'm planning on a few upgrades to my Z1B engine (1075, oversized valves, porting, kz650 buckets, cams, etc) and I was wondering if anyone has converted their stock transmission on their Z1/KZ900/1000 to a six speed setup.
I know the stock gears in my transmission are only case hardened as far as I know, so undercutting those aren't the greatest idea for longevity

I’m very interested in a six speed conversion. I’ll be following this.

Just FYI. I went back and looked at your post when you bought the bike. You might want to confirm what you have so the correct parts can be acquired. The only thing that looked correct for a Z1B is the carbs. You might not have an Actual 1975 Z1B.

Only the frame, engine, and gas tank we're original on that bike, as well as the speedo and tach, everything else was a mixmatch of parts but since then the motorcycle has been restored

There's no six speed conversion i've heard of and i've been around these a very long time.
Nothing wrong with having the stock trans back cut though.
It will cope with a lot more power than you plan to put through it and will probably out last the rest of the bike.

nickacosta wrote: Only the frame, engine, and gas tank we're original on that bike, as well as the speedo and tach, everything else was a mixmatch of parts but since then the motorcycle has been restored

Just a personal opinion. If you have restored a Z1B then adding performance parts is likely to take away from the value. You should consider finding a cheap KZ to play with. Ultimately your money and choice.