Thanks for the replies guys what you have to remember is I am in the UK so it,s not cheaper to build a 400 here. Engine work is expensive here and I have to pay import duty 4%, shipping and vat at 17.5% on any parts I buy from the USA most of the people over here who sell American car parts here are rip off merchants and charge far more than they should for American car parts. it's normally cheaper to import stuff yourself!
The 350 I am being offered is a running motor with a good oil pressure and just needs a rear main seal. I will of coarse check the main bearings and con rods bearings to see what condition they are in while the sump is off. But I hope to just add a decent cam and either put the 11 heads or the heads from my 326 which are 140 heads on there put in my B&M Holeshot 2,000 stall and then try and source a posi rear with some better gears.
I don't have the finances for a full rebuild at the moment this is going to be my winter project I should get the 350 in the next month or so so I will have more info on it then.
67 Firebird 350, TH350 auto Convertible, B&M 3000 TC, 4bbl Edelbrock Performer carb and intake Black Jack headers,disc brake conversion. 10 bolt chevy axle with 3.73's and B&M Rachet shifter.