Hi Michel
Just a bit of advice from an OLD Gezzer (spelling) when you get to mounting the dummy in the cowl chack the balance of your bird and if nose weight is needed, like both of mine, so on my current one I needed several oz's of nose weight so I backfilled it with #6 lead shot mixed with epoxy added a 1/8 ply back plate to it fitted as necessary and when doing a final balance I only had to add 1oz at the fire wall to get the correct nose down with the gear up.
Hope this might help
Cheers Bob T