Check out @Vince P. (Current post on his Amati kit. -Looks like he’s using the lower jig you posted above.
HMS Prince - Amati 1:64 by Vince P. Original 1978 Version
As you know, I just completed the Royal William. The Prince was a ship that was remodeled into the Royal William in the very early 1700's. Amati had a nice kit about 40 years ago of the Prince, but discontinued it long ago. I searched for a source for many years and finally found a fellow...shipsofscale.com
This is why the forum is so great. "Standing on the shoulders of giants". PS just ordered the bigger jig from Hobbyzone - the forum also gives me too many "wishes" that I cannot refuse- any ideas how to boost my self control ?Hi Vince I reall hate to give advice to such a GREAT BUILDER, but I have this keel height problem many times, WHAT I DO IS SPOT GLUE A PIECE LIKE A 1/4 inch X 1/4 inch strip to the bottom of the keel and it is not difficult to remove it without doing any damage as how i remove it after gluing as i have a lot of expeiernce in do overs have tried this method on both PVA GLUES AND CA GLUES AND IT WORKS WHAT DO IS USE NAIL POLISH REMOVER THAT HAS 100% ACOTONE (IT HAS TO BE 100%) PUT IT ON WITH A COTTON SWAB AND USE AND EXACTO BLADE TO PRY IT LOOSE DO NOT EVER FORCE JUST KEEP PUTTING THE ACOTONE ON AND KEEP PRYING IT WILL COME APART WITH NO DAMAGE I HAVE BEEN SUCESSFUl many times