Here's another use for turnbuckles (maybe)
I had to make up a new bracket to mount my replacement Jabsco (deck-wash pump) at the bottom left and also the 60A alternator which piggy-backs on the top of this bracket. The original V-belt tensioners looked like the one used on the 120A alternator bracket on the right hand side but I have always found these a pain to adjust 'just right'. I thought I might try turnbuckles instead. As they are installed in compression, both the locking nut and the threaded frame transfer load onto the eye bolts to give more strength. I also hammered 5/16 stainless nuts into the eyes of the turnbuckles and drilled them out to 3/8 to give a better fit for the mounting/attachment bolts. I was also going to spot weld the nuts into the turn-buckle eyes, but they were a very firm fit, so I thought they shouldn't need it. But I did put captive washers on the mounting bolts just in case (2 b sure, 2 b sure)

It was very nice to be able to adjust the tension of the V-Belt without having improvised levers held by legs or elbows while trying to nip up bolts to secure the adjustment brackets in place.