I'm running some sort of F body long tube headers on my 502ci
The drivers side collector did need a good bit of heating and bending and prying to make the collector dump at the same height as the passenger side BUT there was no clearance issues during installation within my 79 c10 frame rail..... they just absolutely suck butt to change plugs on cylinders 3 and 6 I believe
I've beaten and banged on them + have a socket thats got a ground flat on it to slip past the primary tubes.
You can imagine the excitement I experience installing new plugs when I realize I was 1 rotation off on the hex and then, when the sparkplug is finally torqued to spec, I can't get the socket back off because the flat doesnt line up lol
SHEIT.
Anyhow, not too bad.
I'm running a radiator from a 454 truck, like a 4 core rad from a 90s Era 454 truck, no fan shroud, and flex fan, plus an external oil cooler and my motor will operate at around 195ish on a hot day here in NC. If I spent my time with it and really put the effort in to proper cooling, it would probably run at 180 all day long.
The thing with big motors and overheating at least down here in the south is, if you run crap gas, and like running it on the lean side to save on gas (dunno why you even have a BB to begin with if that's the case) ... they will overheat
Crappy flowing heads, low octane gas, and lean operating conditions are gonna have them big old mountain motors overheating sadly.
Get all the heat off them you can and they'll play nice
Oil coolers and Big radiators with liberal fueling and theyll do just fine.
Anywho,
Sounds like a pretty sweet direction you're headed OP and FastDuramax