Cleveland, Windsor header questions

[84LX89GT]

Alright, this is a weird question so hopefully someone knows.

I'm building a 400 modified cleveland for my '85 LX mustang, i'm going to be adding spacers between the k-member and body (1" - 1.5" depending on what works best) for hood and header clearance since the deck height of a 400 is 1"(if i remember correctly) taller than a cleveland.
Here's my dilemma,
What header should i use and where should i buy it from? They are 2 barrel cleveland heads. Will a large diameter 351w tube header (1 3/4") bolt up to a cleveland with little/no modification or is there no hope for a budget header for this thing.
since the body will be higher up off the engine, 351c swap headers should work but i've only found expensive ones. I could try buying cheap 351m/400 headers using the flange/part of primary pipes and welding 302/351w header pipes to it for the correct shape back but i don't know/think this will work.

Anyone have any ideas? i don't feel like paying $600 for custom headers for this thing, it's being made out of junkyard parts and i can't exactly get this off a stock '78 thunderbird, truck or other 70's land yacht.