The stock water pump sidecover on the V65 Magna is a cheap plastic inserted piece that IMO does not go along with the look of the bike. 
First of all, there used to be chrome replacement covers for that plastic piece which were available through JC whitney. It fell off in 1996 and I have been unable to find one since. I liked the chromed look, (or at least aluminum) and I wanted an alternative. I noticed in my travels that the 1986 V45 Magna had an aluminum cover in that exact spot. It looked to be the same shape, but I wasn't willing to lay out the cash just to test it out.

Then comes Malcolm (The Fringe Kid) on his 1986 V45. With the cast aluminum 'water pump' cover that I was talking about. It washeld on by two bolts.
Obviously, the first question in my mind was "Will it fit the V65 Magna?" Off comes Malcolm's cover faster than he can say "oh my god you're tearing apart my bike!!"
"Relax Malcolm, its only two little bolts...and look, it fits my bike perfectly! heh heh heh Malcolm, didn't you say that you liked the black fringe look on your bike better than the aluminum chrome look???"

Well, thanks to Malcolm letting me test fit the sidecover, I found out that it does fit! So I called a few junkyards to see if they had any. The junkyards wanted $60 for the thing. So I called trusty Discount Honda, and the cover was $41.00 brand new! So I bought one. Of course, I had to have it chromed!

Of course, things can never be that easy. First I made a parts list. The parts I purchased are as follows:
 

Upon receiving all the parts, I inspected the mounting holes, and they were different! Oh well. The water pump mounting hole was in the right spot, but the rear mount where it bolts into the block was different. I took the 'V45' mount into the dungeon and widened out the holes to fit the V65. This worked out well, but since the bolt that holds the bracket in place is open to the motor oil, small amounts of oill tend to drip out after a while. Shades of Harley Davidson!!! I will eventually have a new piece made up that will fit perfectly so no oil will drip.   In the meantine, I just put some teflon thread tape on the bolt, which stopped the drip.

Note the rear mounting bracket. The two holes had to be widened to allow for a fit on the side of the engine.
 The front bracket bolts directly to the water pump bolts. The whole thing could ideally be moved forward about ¼" but that will be another project.
 

 
This is a closeup of the mounting area. To the left is the original mounting system for the black plastic sidecover, and to the right is the modified version.  The original mounting brackets for the plastic cover can be seen. The rear one needs to be removed and replaced with the new one. The front original bracket can stay where it is since it does not interfere with the new cover or brackets. The new front mount bolts directly on.

The Result

Addendum:  Perfecting The Mounting & CHROME!

Yes, I was not happy with the barely noticible gap that existed.  After careful measurements, I determined that the whole thing could be moved forward by .30"  So I went to good old Reynolds Welding Lab, and spoke to George, who was more than happy to help.  On the photo at the left, you will see the unmodified front bracket (right) and the modified one.  This consisted of breaking away the original weld, and widening the slot that the cylindrical piece fit int.  Then it was re-welded.  The rear bracket (shown in the photo on the right) had to be cut to allow George to weld two new pieces to the mounting area.  Once those pieces were welded, the holes were drilled in the proper locations.  To find the proper location of the hole, I used a spare upper engine case I had laying around.  This helped the positioning a lot.