IMHO the Borg Warner T15 behind the Dauntless is the optimum 3 speed into a flat fender V-6 jeep. The Jeep T15 requires an adapter plate between it and the BOP bellhousing. Myself I have both an AA adapter plate and a NOS Trans Dapt that are designed to fill the need. Yes both adapters have distinctly different designs. A new Advance Adapter is pretty steep in price. The Trans-Dapt is long out of production and quite rare. I've been asked several times to sell one of mine but I decline for now. So I've been considering to modify a stock T14 adapter for T15 applications. I do believe the stock adapter could be modified to produce an excellent adapter. The changes would need to be well done and precise. As you know the stock adapter already fits the BOP bellhousing pattern. It also fits the Jeep T15 bolt pattern. First one needs to address the thickness problem. The adapter needs to be reduced from 2-5/8" thickness down to 1-5/8" thickness. Basically the hollow middle area of Jeep T14 adapter needs to be cut out and removed. Milling of the 2 separate halves perfectly flat again is ideal but a precision job of grinding should suffice. Next the two haves need to be re-aligned and welded back together. 55% nickle arc welding rod works wonders on this type of casting. Of course a chamfer for deep weld penetration is required. Secondly the T14 index bore needs to be re-sized to fit the larger T15 bearing retainer. This must be precisely bored on center. Upon installation the original T15 bearing retainer is re-used. The Jeep T15 bearing retainer simply indexes into the modified adapter and it is long enough to enter at correct depth into the Buick bellhousing. What do you all think ? Remove 1" from the middle: (# 941186) Remove these shifter bosses while were at it: The bellhousing face: Note the ingenious step design used to index the adapter into the BOP bell. No other T-15 adapter that I've ever seen uses this simple design. The transmission face: Note the 4.25" bearing retainer bore will need to be increased to 4.686 (same as GM or T15) After modifications, a standard T-15 bearing retainer is used to reach into the BOP bellhousing Bearing retainers: Standard T-15 bearing retainer = 4-3/4"" long with 1.310 or 1.405 bearing sleeve GM # 3741458 bearing retainer = 3-1/4" long " with 1.37" bearing sleeve T15 bearing retainer with sawed off bearing sleeve is required for an AA adapter.