[RichH]

Anywhere but forward under the vee berth.
Some Tayanas are built with tanks under the vee berths - not too good! Also consider if you add extra ground tackle .... this plus the added weight from the forward tanks will greatly enhance ''hobby-horsing'' (extreme pitching) of the hull.
Keep the weight in the middle, keep the ends light.
You might want to pose the same question on the Tayana Owners Group here on Sailnet. I have a bow tank on my Tayana and am seriously thinking to eventually rip it out and relocate to the middle.