[slyalfa]

That is what I was thinking. but also add a triangle too so the side of the cap is locked in.
And mabee weld the caps to it...
The bolts of the caps would need to be longer or the caps shaved down.
even if it is just a bolt on it might make sence to mill the caps down where it mates to the bedplate as the bed plate will add back the thickness. Then the fit will be dead on. Right now the caps are cast on that end and the fit would be vey bad. and some caps 164s have a flate spot to mount the oil pick up on one cap.

if the caps are milled it might be good to leave a rased part in the center to help lock the cap.
a round peg that fits in a drilled hole in the bedplate.