I should of disqualified you from answering Pat----Yes its a main bearing cap, but its not a bearing spacer--its actually a steel repair part for a spun main in an aluminum block, the block gets bored out to the out sode dimension, cap register in block machined down for the taps and then re alighn bored with a new rear cap--

Repair for aluminum hemi------Kind of like a hemi main sleeve???????????//almost bow tie shaped!!!!!!