Won't upshift

[M.Alphonse]

I'm hoping I can get some help with a problem I seem to have created.
I was fixing some leaks in my transmission, and replaced a couple of O rings on the kick down solenoid and something that looked like a heat sensing switch. I fixed the leaks but now my trans won't shift up to second. I must have done something wrong, it was working fine before. It's a 1985 380 SL.
I've taken it apart again to check that the O rings weren't damaged. Everything looks right. In checking around I found that I had no power to the kickdown switch under the gas pedal. That would suggest the fuel pump relay, but how did I get there, just changing some O rings. I've looked around online a lot and have learned a little but Auto transmissions are not my strong suit.
Thanks in advance for any suggestions.