Those 99 forks from a CBR900 should install by using a triple tree from an 1100 or 1200. I believe they are 41mm tubes so the 1200 triple tree will bolt right up to your 76. You will need to modify the stops. You will likely need to space the wheel and calipers to fit whatever you choose. The stock 77 forks are flimsy even with a fork brace.
There are older posts about this. A good one by dangeruss.
Whatever I suggest here should be given ample time for a moderator to delicately correct. I apologize in advance.
77 WING, 1200 engine with 77 heads, cams, gl1100 foot pegs, Magna V65 front end, 764A carbs, [-gone Suzuki M109 monoshock--, replaced with gl1100 shocks] gl 1200 swing arm, gl1500 final drive, wheel and rear brakes Valkyrie seat, Meanstreak tank, Sportster pipes, Power Arc ignition off crank.
77 Wing. black
83 Wing, in pieces
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