Question: What is the difference between F32W07 F35W08 and F32W07B F35W08B or the difference between F32Y07 F35Y08 and F32Y07B F35Y08B?

(20200418... edits above... strokeouts superceded by type in red.  

Answer: The Floats are the same except for the color. The forward mounting bracket on the "B" version of the floats was designed to fit the early versions of the Beaver 40-60 ARF built prior to 20050101. These brackets have a three hole mounting system to match three pre-drilled holes in the bottom of the Beaver 40-60 ARF fuselage.

Since 20050101 the Beaver 40-60 ARF has four holes predrilled in the bottom of the fuselage for the standard main gear set that comes with the Beaver 40-60 ARF. The spacing of the holes in the bottom of the fuselage may not match the holes in the mounting bracket that comes with your floats. If it matches, you are good to go... if it does not match, four new holes will have to be drilled... this is not a big job if you follow the procedure outlined below.

Procedure:

Remove the forward mounting bracket from the float box. Turn the fuselage upside down and locate the pre-drilled holes in the bottom of the fuselage. Hold the mounting bracket with the flat non-tapered edge facing the engine end of the fuselage. Check the holes in the bracket vs the holes in the fuselage. If they match, attach the bracket to the fuselage with the screws provided. If they do not match, carefully center the mounting bracket and mark the location of the bracket holes on the fuselage using a ball point pen. Remove the bracket and examine the four pen marks. Plug the factory drilled holes in the fuselage with clear or white silicone. Use a 3/32" drill bit to make four new holes in the fuselage at the loction of the pen marks. 

Turn the fuselage upright and note the location of the four new holes in the landing gear flat plate in the bottom of the fuselage.  Locate the extra flat plate provided with the floats. Epoxy this plate into place inside the fuselage on top of the four holes you drilled. Let the Epoxy dry. Now turn the fuselage back over and drill the four holes again.

Attach the front bracket for the floats (flat non-tapered edge facing forward) to the fuselage with the four screws provided.