Okay - welcome to the Clark TK22 upgrade club - these things are not plug and play and require a bit of technician work to get running well. My experience has been that the 8 pin connector as supplied in your Leo is probably not wired to reflect the needs of the TK22. I have had to completely re-wire my Leo 8 pin connector so that it matches the connections on the wiring diagram on clarks website. Try checking this out first.

cheers

CaptB