Welcome to the forum sixten.
Here in the states we never had a Z500. We are going to have limited experience with racing one. There are a few racers here, but we dealt with the KZ/GPz line of bikes. I did some racing on a 500, but it was a Yamaha. Not sure that's gonna be any help. I can tell you I didn't run a cooler on it, if that helps at all.
And Welcome again.
Don't be ridiculous! It's only a flesh wound!
Wife's little bike... 1984 GPZ 550 Kerker and DynaJet stage I kit
Wife's BIG bike...... 1981 GPZ 1100 Kerker and factory FI
The Z500 is almost same as the 550, only with a 3mm smaller bore. Tons of guys raced those bikes so there should be lots of info available. Corey Clough is a member here with lots of experiencing racing 550's. You might want to look him up and pick his brain.