Overdrive Transmission Suggestions: Auto vs. Manual

[SAC]

So I'm one of the unfortunate left high and dry by the closure of Keisler Engineering.  I ordered an automatic overdrive back in October, with the promise of delivery by January 6, though the salesman didn't think it would really take that long.  The delivery date came and went, and now I have to file a claim to attempt to get any of my money back.  

Now, I have a disassembled project in need of a transmission.  It looks like there are several Tremec-based 5-speed kits out there, most of which appear fairly complete.

I'd really rather keep the auto trans, especially with my factory console and Slapstik.
Anyone with any experience adapting a 4L60E?  This is the transmission the former Keisler kit was based on.  I think I may be able to piece a kit together using a performance-built transmission, a Quick Time bellhousing, and some sort of control unit.
Issues that I anticipate facing with this selection: shifter and speedometer hookup, and the need to fabricate a crossmember.  I don't even know where to begin for selecting a flexplate.

Any words of advice for either manual conversion or automatic adaptation?

[cdr]

i went with a518 conversion call  http://www.transmissioncenter.net/

[SAC]

Thanks for the input.  The Mopar magazines have spoken of fitment issues with the 518 transmissions for years.  Did you have to modify the floorpans?

[cdr]

yes on the pans.patc also has the 4l60e call them

[Cooter]

The 4L60E is basically a 700R4 that's electronic.
not the strongest for high horse, high torque apps.
for cruisers, works well.

The 518 is basically the '727' overdrive, but the overdrive unit is the weak link when upgraded with high line pressures.
the 500 is basically the '904' overdrive.
46RH/'RE is another name for the 518 unit in later years.

[SAC]

The 4L60E is basically a 700R4 that's electronic.
not the strongest for high horse, high torque apps.
for cruisers, works well.

I understand this.  The 4L60 fits better than the 4L80 or any of the Mopar Overdrives, so that's why I'm looking at it.

[John_Kunkel]

The size advantage goes to the 700R4, the OD is inside the main case instead of hanging off the rear like the Mopar offerings.

The 700R4 can be built to take a lot of power...like most GM products more time has been devoted to improving it for the performance world.