A subject near to my heart. I've use a pair of 49s for over 20 years for WL fishing. Though not int he past 5 seasons, though. Its tough to get crew these days that doesn't mind cranking in 400 ft of wire 25 times per trip.
Anyway, my 49s were among the first with the aluminum spools, which does not work out very well with wire, over the long term. The anodizing and then the aluminum of the spool itself will react with the wet wire, pitting the spool and wrecking the line.
What to do is to either source an old-time chrome on brass spool for your reel (if it does have the aluminum spool), or to paint your spool with two coats of Rustoleum paint, letting it dry one week between coats.
I like 50 Dacron for backing, then a Spro 130lb swivel, then the wire line. The leader goes to the wire with the same Spro swivel.
You can mark the line in several ways, including telephone bell wire wrapped around youy line at the intervals you choose.