Hi GDavies,
What I would have done before all this, would have been to ask here first, then get to work after.
But it's too late for this, so here's what I'd reccomend.
First, the shellac you removed would have taken you maybe 10 minutes to deal with with the proper solvent (methyl hydrate). Light rubbing would have removed the surface layer, maybe more rubbing would have removed all of it; in any case it would have been quicker.
Second, removing the old shellac was not necessary to give it a new beauty. Thing is with shellac, if you just clean the surface with Methyl hydrate, then gently rub it with the finest steel wool, your surface is ready for new shellac. The new shellac with partly disolve the old, mix with it, and the surface will be "nice" again.
My advice at this point is to find dark-colour shellac (red ideally, but I suppose orange would be possible too), and bring back the stock to as-close-to-original as possible...
But, it's your rifle, so...
Louis