I looked through this topic from the beginning, but couldn't find any real details of the head-rigging posted, but...
normally the fore-stay(s), and the fore-topmast stay(s) go to fixed point at the base of the bowsprit and not quite the end of the bowsprit respectively. The other stays go through a sheave or bee-hole in the jib-boom and flying jib-boom (if there is one) and either down over the dolphin-striker and back to, or straight back to the bulwark on either side of the bowsprit (knight-heads). They're adjusted by bullseyes and lanyards, (or rigging-screws on larger ships by this time frame).
Yours is a steamer built by a merchant ship-builder basically conscripted into being a warship. You're right to assume her building and rigging would follow what they've built before clippers and merchant steamers.
There's a lot going on in the head-rigging, and it was evolving through the 1840s through the 1860s.
On purpose-built warships it eventually evolved into this:
View attachment 500597
A lot of this ported over from merchant carriers (clippers), the navy used less iron-work and chain through the 1840s.
Welcome to the world of thinking you have it only to find out it wasn't that way, after you've built it.