Bearing housings assembled on the main drive plate also one inch thick. You can see here that we have machined an arc that accommodates angle adjustment as the whole assembly has to be aligned as closely as possible to the propeller shafts in the boat. You should see a small rectangular white part between the housings. This part hooks up with the clutch and prevents the outer clutch-body from spinning, whilst still enabling slight clutch-body movement which is recommended by manufacturers. The other two holes in the plate enable it to be bolted in position, one actually prevents the angle from being adjusted once the positioning is set (prop shaft alignment). If you are wondering why there is a whole beneath the white rectangular clutch tab, it's because the original setup used a smaller clutch and we had a part which bolted in that position that served as the clutch-body locking lug.
Just in case you are wondering whether or not the camera is playing tricks. Not all of the work on this project has been carried out in the machine shop. Parts like the little white tab did not have to be precision machined, and in fact I simply fabricated small bits like this and installed them on the fly as the need arose. My machinist would probably cuss me, but, needs must! Besides, I could not always afford his bills, nor the waiting time. As it is I am having to work in the machine shop as an assistant from time to time to help pay off some of my bills! So yes, the white tab is not perfectly straight, it's a milimeter or so out on the alignment-diagonal, but it doesn't matter one iota! To put it into perspective, when we machined this stuff, we were working to 10-1000th of one millimetre on the the CNC machine for critical surfaces and said 'what-the-heck' on 10-100th of one millimetre in non critical areas. Then outside the machine shop when I'm doing the real work.... where's my hand-drill!!! ha ha ha....