Every time I see any kind of top with 4 rod holders in the center, when they had plenty of room for 6 or 8, I just scratch my head and wonder why. When I had an arch modified to fit my Grady, the fabricator charged $20 each for good quality gold rod holders, including the welding. Best $160 I have ever spent on a boat, and now I wish I had added 3 to each support leg.
The 1801 is a small cockpit, so don't let tee top rod holders point back at an angle that interferes with casting. 15 degrees at the most.
You may not be doing curtains right away, but go ahead and have the builder put on the slide track for the top of a curtain set. If he doesn't do curtains, as well as tops, get a canvas person to advise you on placement.
If you add and electronics box, snake as much wiring as you can before the top is bolted to the boat/console. Figure out exactly how many wires you need, then double it. If you boat at night, you will want your all around white on the top, so that you are not blinded every time you look over your shoulder.