Thats what I was afraid of, it would only make sense for them to be bigger too. I have read alot of your posts on what you did with 525sc's and based on reading your info I planned to go to the 420 if I did a blower upgrade. But I am going to be limited to what i can fit under my hatch it looks like.

This year I kept getting small blue remnants of the leak lock in my carbs (seats) to the point i put them small stone filters in there.. for fuel fittings I think I`m going to stick with teflon tape.

My old line set up to the carb was a -8AN line to a Y in the middle of the valve cover, then fed both carbs, When I pulled that apart to put the dual feed set up on to clean it up a bit, mine had little tiny filters inside the feed ports on the carbs backed by a spring. I was advised to remove them since I have a 10 micron fuel filter and they weren't necessary or overkill. Sounds like thats something you are looking for, those little tiny screen filters

This is a pretty big" thread" for thread sealer. Loctite 567 seems to work for me, thicker than Permatex, the Permatex has to be kneaded together before using. If you want that ultimate seal use some Loctite 545.

Just my Nickel's Worth.

Watch out for adding other filters into your fuel system. They can cause lean conditions. Remember you want balance of filtering and fuel flow, there is a trade off. You can never have the greatest filter that filters 100% of the smallest materials because that will restrict fuel flow. Also too many added fuel filters will restrict fuel flow and is very hard on fuel pumps. Just saying

I didn't add any fuel filters, just replaced the one that was there with a better flowing filter, and removed those 2 little small screens that were in the feed ports of the carbs

I'm no expert on filters/flow rate etc, but my tech told me to run a filter ahead of the electric pump as the tolerances are so tight it doesn't take much tank sediment to cause havoc.

Yes some pumps say to run a pre filter of like 90 microns I think to get debri out that could damage the pump

That's correct about any filters coming out of the fuel tank before the electric fuel pump. They need to be 80 to 120 microns rated. That micron rating will not filter the small crap. Also electric fuel pumps hate to pull fuel - they do a whole better pushing fuel. If a filter before the fuel pump is too restrictive (finer micron rated filtering) it will shorten the life of it plus cause fuel flow restrictions.

The Mallory pump I believe is a specific pump that wants a pre pump filter as the littlest particles can kill it. I am pretty sure the holly has a built in screen to keep certain size debri out