Eric,
I called Beckmann Technologies a month ago and told them my symptoms. I was planning on pulling and shipping my throttle actuator to them. They disagreed and said to check the throttle cable free play. It should be 1/4" They also said the throttle position switch (none on my model) and the neutral safety switch all could cause problems. I have the necessary free play and I replaced the NSS and the brake light switch. So far, every thing points to the OVP relay.
Anziani

'93 300CE 170K
'95 E420 117K