T56 in a 70 convertable
 

My brother in law has a 70 convertable. The car is sweet. Bright yellow all redone, the car looks new. It's got a 351c with a four speed. The problem is it revs so high on the highway it's pulling 4000 at 70 w/ 390 gears. I talked to d&d and he said I would need a smaller flywheel, I'd have to shorten the driveshaft, build a crossmember, and convert the linkage to either hydraulic or cable. I'll be doing the work. There were a couple of things I was wondering. Has anyone done this swap before? Where would I find a linkage conversion like the guy at d&d spoke of. Also what would I use for a speedo cable, Is'nt the t-56 an electronic speedo? It has a mach 1 console so I have room to play with as far as shifter location. If I have to I can remove the center of the console and move the shifter location back a couple of inches. this car would be sweet with a 6-speed. Any input would be greatly appreciated
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