Garhauer Mast Plate MS-6 questions (Bristol 30 cockpit lines)

[svsonora]

I'm doing a project where I'm going to run my lines to the cockpit.

So if you've seen a Bristol 30 or 29, you'll see that the mast step is sitting on top of a fiberglass box. I drilled into it with a 1/8 bit and it was solid - either solid glass, or some sort of dense wood inside. I think if I bought these mast plates from Garhauer and through-bolted it from both sides, they might work.

I was wondering if anyone has used them. They seem a bit small. If they are 7.5" long and only 1.125" wide (since its bent, I'm thinking the area where the blocks would shackle to would be about 0.8" wide) Seems like they might be made for a 25 foot boat instead of a boat my size.

Alternative is to have plates like these custom made, but I'd much rather get them off the shelf. Or use these one.

My question is, are these sized properly for my boat? If not, any alternatives?

Here is an image of my sailboat few years back. She currently has a hard dodger (with space for line to pass through), but this picture shows the 'box.'
https://i.imgur.com/YSonCVb.jpg

I'll post a separate thread asking for advice on many other issues I've spotted on this project.