I can't remember exactly why I needed the spacers to begin with, but I think the spacing was approx 5/16 - 3/8. I thought it had something to do with the adapter plate. Also, the BOP converter was threaded and the chevy converter wasn't. I installed the trans about 5 months ago and haven't driven much since then. I will have to get under there to measure it and check it out. Maybe the converter is too far away from the flex plate? If I take the spacers out, will it matter if there is that extra sapce on the spline of the trans?