Besides the 25% more weight than your 5-speed ZF, the mounting problems, rigging a shifter that will work and the physical size of the thing, the Ricardos are in very short supply. The last one I know of that sold (to a kit-car friend 2 months ago) was $16,000 + shipping. An RBT 6-speed is very little heavier than your 5-speed, fits without altering the back end of the Pantera, hooks up to your existing shifter and costs about the same.
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