which cable is gubbed? the short one between the remotes & the tacho, the tail on the remotes or the main loom?
If the short one, worst case you can make your own by either cutting the connector (if it is a "Yam multiplug" & substituting your own homemade lead- If, however it is a bunch of bullet connectors hanging out the remotes, just make the lead.
Memory says the Yam tacho has screw post terminals, so a "value" box of bullets & / or eyes will work nicely with a length of 3 (or 4 if you want the guage to light as well)
Maplin & the like sell the crimp tools for the eyes / studs. but I tend to judiciusly use Mole type grips
Hope this helps.....