Model 51 - Reel seat or Deckhand style. Penn reels Set the opening the mounting post to the widest and measure. These are 1-1/4 inch center to center
Model 51 - PENN small - Fathom, and Squall 12, 15, Penn GS 525
Penn 16VS Squall Lever Drag 2 Speed Reel, Offshore Reels - Canada
Penn 525GS reel tuning guide
PENN Squall Lever Drag 2 Speed Reel
Model 51 - PENN small - Fathom, and Squall 12, 15, Penn GS 525 – BoilingTuna Products
PENN FATHOM II LEVEL WIND REEL SPECS
Penn 16VS Squall Lever Drag 2 Speed Reel, Offshore Reels - Canada
Penn Internal and External Parts