So, I have an 81' and I am doing an instrument panel swap so that I have a Tachometer. I have the instructions for that from Old Volks Home, but what I want to know about is the speedo cable. The one in the van now screws into the back of the speedo, but the new cluster has a push-in type of connector. I want to know if I should buy the long replacement cable that bypasses the EGR box, or if I should just buy the 86-91 EGR to speedo upper cable. At BusDepot.com it would be cheaper just to buy the bypass cable than to buy the upper. What would happen if I bypassed the box? Bus Depot says it just means that the EGR light won't come on at the scheduled intervals, nothing else.