This thread obviously got missed when it was timely but I thought I'd post on it for the benefit of anyone else trying to do it. I don't have a diagram but here's how we do it.
1. Completely remove the 15 amp/120v input cord and grip.
2. Remove the L6-30P input cord from the grip and remove the wires. (remove the ground, the black L1 that goes to the SSR terminal, and the white L2 wire that goes to the red wingnut. Replace the wirenut temporarily to not lose track.
3. Insert your 14-30P appliance cord into the open grip ensuring you have at least 6" of stripped back insulation.
4. The black L1 wire should have a ring terminal crimp, which goes onto the SSR terminal that was originally fed by the black wire.
5. The green ground goes to any green screw, again via crimped ring terminal.
6. The RED wire goes to the Red Wirenut. Note that this is a little confusing if you don't pay attention. The incoming red is L2 hot which is what the previous cord used the white wire for. It just looks weird to combine a red wire with those two white wires but that's what you do.
7. The new incoming white wire is the Neutral. The only place this needs to connect is the pump outlet's neutral This is where the original 120v white wire connected previously. We cut this white short and crimp and 1/4" spade QD onto it.
The last order of business is to feed the L1 hot into the pump relay. This is originally where the 120v black wire attached to. This can be tapped off of the SSR terminal where the Large black input wire goes. However, the BETTER way to do it is to attach an inline fuse holder wire to that SSR terminal with a 5-10 amp fuse. On the other side of the fuse holder add a black wire that goes to the pump relay. Lastly, the small black wire that is already on the SSR terminal feeds the circuit board to power up the display/logic board. I remove that from the SSR terminal and wirenut it to the output of the inline fuse. That way all the low current stuff is fuse protected.
