Years ago, I put in a 6 speed gear set in my 00 FXDS TC... Rev-Tech 6 speed gearing... FIT right into my HD 5 speed box...JP Cycle also had a full 6 speed tranny replacement from Rev-Tech...
I bought the full conversion gear set with the trap door...
Many saying in those days,,,,,it was not a good unit... I MUST Have gotten a Good one

, as I put on more than 60,000 trouble free miles on that conversion. Redline ShockProof Heavy was the choice for lube then and Required in the early Baker conversions HD did for warranty of 50,0000 miles on them.
There was Choice of the final ratio for 6th gear on my purchase...
Might check to see... Conversion gear sets sold for 950 to 1350 back then.
Mine was the better full unit and it was 1350. (memory?)
signed....BUBBIE
Got on the phone with JP...
Their on-line is difficult....
CS helped out.
Here is some information...
RevTech 6-Speed Overdrive Transmission | 620-241 | JP Cycles
see if this will help you out... MUCH Less in Dollars for a complete 6 speed tranny or a gear set.
signed....BUBBIE
Click on fitment then on the HD+ and it will list the bikes it fits.
Rivera Primo Powerdrive 6 Speed Gear Set | 630-988 | JP Cycles
Also this gear set :::: click on the fitment then on the + harley and it will show all the HD's it fits...
Your Welcome
signed....BUBBIE
IT does fit....Touring Electra Glide Standard FLHT : 1995–2006