I have drawn up a bridge for the 49 reel and plan to have it lasercut from 316 stainless steel.
The same can be done for the small senators. In this way the (new) bridge post can be screwed into the bridge and locked with locktite. If there is enough space between the bridge and the spool, it may even be possible to place a nut there to further stiffen up the bridge post.
The bridge post has a flange that sits against the bridge. This is 7.2mm i diameter. The corresponding hole in the gear sleeve is a bit more. This can be opened up to 8.2mm without problems. The flange on the bridge post can be enlarged to 8mm in dia. This will help a bit on rigidity.
I know that this is taking it to the extreme and this modification is unneccessary unless you do all the other modificatons in the book.
The reels I am thinking of is the 112, 112H and the 113. The jigmaster 500 may also benefit from a custom stainless bridge.
Any thoughts about this?