The E15 and E20 are substantially different; different number of speeds, different wiring harnesses, etc. Without a complete re-wiring, "one board" couldn't fit both.
Not to be a party pooper, but... I don't think there is a problem to solve here with new control boards. Either keep with the factory control systems and replace blown parts, redo bad connections, etc. or go for a complete redo with a "modern" electronic motor controller.
*The lift motor and headlights however do tap the battery pack, so these would be areas of (modest) improvement. I'm not sure anyone has real evidence that the batteries end up badly out of balance as a result of the taps... the charger generally does enough equalizing to take care of this.
bill-wallace att net wrote: <snip>
The idea of a new control board that can be plugged into existing wiring sounds really great to me and it seems a few others.
<snip> -- Jim Coate 1970's Elec-Trak's 1998 Chevy S-10 NiMH BEV 1997 Chevy S-10 NGV Bi-Fuel http://www.eeevee.com