OK, reversed directions and ordered the Colony locking hardware for the flanges at the heads.

Did a test-fit today (not sure how I'm going to get this thing off again to install the gaskets and sealant!) and to answer the question as to the difference between the 1977 and 78-84 exhaust (at least as far as I can tell) might be this: I have contact in 2 places; at the cone acorn nut, and at the highway peg mount. I don't think either will be an issue, but please let me know if I'm wrong (preferably before my hardware arrives and I install this thing!).

Acorn contact:


correct pipe:


Is it possible I have the wrong (length) acorn nut there?

Here is the highway peg mount interference:



and here is what it looks like altogether from the side:

 

No Shovel I own has Nuts on studs at the Cone Cover.. Socket head cap screws..
That may Not be an O.E. Highway peg mount..My '79 Clears by a Bit.. If Aftermarket Mount...I grind to Clear... after all...China will crank out a New One .. In fact probably the Next one could be Better...or Worser...

 

Perhaps the highway peg mounts are on upside down?

 

Looks like the acorns are an FXB thing: (which is cool)

 

My FXB had acorns, and the peg mounts are mounted correctly.

 

I have done that...to get Pegs closer or Farther Away!! It's about comfort for Me...

 

LOL - they already seem short to me.

 

Try flipping the mounts, they will be higher, and solve your interference problem too.

 

I doubt Higher due to Offset of holes..farther away...and...No Interference..again offset holes

 

I was visualizing a line through the two mounting holes. Right now the peg mount is below that line. Flipping it will put it above that line. Opposite with the interference. Yes?